<PAGE>   1
 
   
   AS FILED WITH THE SECURITIES AND EXCHANGE COMMISSION ON DECEMBER 2, 1994.
    
 
                                                       REGISTRATION NO. 33-56195
- --------------------------------------------------------------------------------
- --------------------------------------------------------------------------------
                       SECURITIES AND EXCHANGE COMMISSION
                             Washington, D.C. 20549
                             ---------------------
 
                                AMENDMENT NO. 1
                                       TO
 
                                    FORM S-3
                             REGISTRATION STATEMENT
                                     UNDER
                           THE SECURITIES ACT OF 1933
                             ---------------------
 
                               KIRBY CORPORATION
             (Exact name of registrant as specified in its charter)
 
 
<TABLE>
          <S>                                               <C>
                       NEVADA                                    74-1884980
          (State or other jurisdiction of                     (I.R.S. Employer
           incorporation or organization)                   Identification No.)
</TABLE>

 
             1775 ST. JAMES PLACE, SUITE 300, HOUSTON, TEXAS 77056
                                 (713) 629-9370
    (Address, including zip code, and telephone number, including area code,
                  of registrant's principal executive offices)
                             ---------------------
                            GEORGE A. PETERKIN, JR.
                                   PRESIDENT
                               KIRBY CORPORATION
                        1775 ST. JAMES PLACE, SUITE 300
                              HOUSTON, TEXAS 77056
                                 (713) 629-9370
                    (Name, address, including zip code, and
          telephone number, including area code, of agent for service)
 
                                   Copies to:
 

<TABLE>
<S>                                                        <C>
                HENRY GILCHRIST                                 THOMAS P. MASON
JENKENS & GILCHRIST, A PROFESSIONAL CORPORATION              ANDREWS & KURTH L.L.P.
          1445 ROSS AVENUE, SUITE 3200                     4200 TEXAS COMMERCE TOWER
            DALLAS, TEXAS 75202-2799                          HOUSTON, TEXAS 77002
</TABLE>

 
                             ---------------------
     APPROXIMATE DATE OF COMMENCEMENT OF PROPOSED SALE TO THE PUBLIC: As soon as
possible after the Registration Statement becomes effective.
                             ---------------------
     If the only securities being registered on this Form are being offered
pursuant to dividend or interest reinvestment plans, please check the following
box.  / /
                             ---------------------
     If any of the securities being registered on this Form are to be offered on
a delayed or continuous basis pursuant to Rule 415 under the Securities Act of
1933, other than securities offered only in connection with dividend or interest
reinvestment plans, check the following box.  /X/
 
     THE REGISTRANT HEREBY AMENDS THIS REGISTRATION STATEMENT ON SUCH DATE OR
DATES AS MAY BE NECESSARY TO DELAY ITS EFFECTIVE DATE UNTIL THE REGISTRANT SHALL
FILE A FURTHER AMENDMENT WHICH SPECIFICALLY STATES THAT THIS REGISTRATION
STATEMENT SHALL THEREAFTER BECOME EFFECTIVE IN ACCORDANCE WITH SECTION 8(A) OF
THE SECURITIES ACT OF 1933 OR UNTIL THE REGISTRATION STATEMENT SHALL BECOME
EFFECTIVE ON SUCH DATE AS THE COMMISSION, ACTING PURSUANT TO SAID SECTION 8(A),
MAY DETERMINE.
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- --------------------------------------------------------------------------------

<PAGE>   2
 
   
                               KIRBY CORPORATION
    
 
                                DEBT SECURITIES
 
                             ---------------------
 
     Kirby Corporation (the "Company") may offer at any time, or from time to
time, its debt securities consisting of debentures, notes and/or other unsecured
evidences of indebtedness (the "Debt Securities") with an aggregate initial
offering price not to exceed $250,000,000. The Company will offer the Debt
Securities to the public on terms determined by market conditions. The Debt
Securities may be offered separately or together, in separate series, in
amounts, at prices and on terms to be determined at the time of sale and to be
set forth in supplements to this Prospectus. The Debt Securities may be sold for
U.S. dollars or one or more foreign or composite currencies and the principal
of, premium, if any, and interest, if any, on the Debt Securities may likewise
be payable in U.S. dollars or one or more foreign or composite currencies.
 
     The terms of the Debt Securities, including where applicable the specific
designation, aggregate principal amount, denominations, maturity, rate (which
may be fixed or variable) and time of payment of interest, if any, purchase
price, any terms for mandatory redemption or redemption at the option of the
Company or the holder, the initial public offering price, and the names of any
underwriters or agents and any other terms in connection with the offering and
sale of the Debt Securities in respect of which this Prospectus is being
delivered, will be set forth in the accompanying Prospectus Supplement (the
"Prospectus Supplement").
 
     The Debt Securities may be offered through underwriters, agents or dealers,
or directly to purchasers by the Company. If an underwriter, agent or dealer is
involved in the offering of any Debt Securities, the underwriter's discount,
agent's commission or dealer's purchase price will be described in an applicable
Prospectus Supplement, and the net proceeds to the Company from such offering
will be the public offering price of the offered Debt Securities less such
discount in the case of an underwriter, the purchase price of the offered Debt
Securities in the case of a dealer, and less, in each case, the other expenses
of the Company associated with the issuance and distribution of such Debt
Securities. See "Plan of Distribution."
 
                             ---------------------
 
        THESE SECURITIES HAVE NOT BEEN APPROVED OR DISAPPROVED BY THE 
         SECURITIES AND  EXCHANGE COMMISSION OR ANY STATE SECURITIES 
          COMMISSION NOR HAS THE SECURITIES AND EXCHANGE COMMISSION
             OR ANY STATE SECURITIES COMMISSION PASSED UPON THE 
               ACCURACY OR  ADEQUACY OF THIS PROSPECTUS. ANY 
            REPRESENTATION TO THE CONTRARY IS A CRIMINAL OFFENSE.
 
                             ---------------------
 
     This Prospectus may not be used to consummate sales of the Debt Securities
unless accompanied by a Prospectus Supplement.
 
                             ---------------------
 
   
                The Date of this Prospectus is December 2, 1994.
    

<PAGE>   3
 
                             AVAILABLE INFORMATION
 
     The Company is subject to the informational requirements of the Securities
Exchange Act of 1934, as amended (the "Exchange Act"), and, therefore, files
reports, proxy statements and other information with the Securities and Exchange
Commission (the "Commission"). Such reports, proxy statements and other
information can be inspected and copied at the public reference facilities
maintained by the Commission at 450 Fifth Street, N.W., Washington, D.C. 20549;
at its New York Regional Office, Seven World Trade Center, New York, New York
10048; and at its Chicago Regional Office, Northwestern Atrium Center, 500 West
Madison Street, Suite 1400, Chicago, Illinois 60661. Copies of such material can
be obtained at prescribed rates, by writing to the Public Reference Section of
the Commission, 450 Fifth Street, N.W., Washington, D.C. 20549. Such material
can also be inspected at the American Stock Exchange, 86 Trinity Place, New
York, New York 10006, on which the Company's Common Stock is listed.
 
     This Prospectus constitutes a part of a Registration Statement on Form S-3
(together with all amendments, supplements and exhibits thereto, the
"Registration Statement") filed by the Company with the Commission under the
Securities Act of 1933, as amended (the "Securities Act"). This Prospectus omits
certain of the information set forth in the Registration Statement (in
accordance with the rules and regulations of the Commission), and reference is
hereby made to the Registration Statement and related exhibits for further
information with respect to the Company and the Debt Securities.
 
                INCORPORATION OF CERTAIN DOCUMENTS BY REFERENCE
 
     The following documents previously filed by the Company with the Commission
are incorporated in and made a part of this Prospectus:
 
          (i) Quarterly Reports on Form 10-Q for the quarters ended March 31,
     1994, June 30, 1994 and September 30, 1994; and
 
          (ii) Annual Report on Form 10-K for the year ended December 31, 1993.
 
     All documents filed by the Company pursuant to Section 13(a), 13(c), 14 or
15(d) of the Exchange Act subsequent to the date of this Prospectus and prior to
the termination of the offering made hereby shall be deemed to be incorporated
by reference in this Prospectus and to be a part hereof from the date of filing
of such documents. Any statement contained herein or in a document incorporated
or deemed to be incorporated herein by reference shall be deemed to be modified
or superseded for purposes of the Registration Statement and this Prospectus to
the extent that a statement contained herein or in any subsequently filed
document which also is, or is deemed to be, incorporated by reference herein
modifies or supersedes such statement. Any such statement so modified or
superseded shall not be deemed, except as so modified or superseded, to
constitute a part of the Registration Statement or this Prospectus.
 
     The Company will provide without charge to each person to whom this
Prospectus is delivered, including any beneficial owner of shares of Common
Stock, on the written or oral request of such person, a copy of any or all of
the documents incorporated by reference herein (other than exhibits to such
documents unless such exhibits are specifically incorporated by reference into
such documents). Request for such copy or copies should be directed to G.
Stephen Holcomb, Vice President, Kirby Corporation, P.O. Box 1745, Houston,
Texas 77251-1745; telephone (713) 629-9370.
 
                                        2

<PAGE>   4
 
                                  THE COMPANY
 
GENERAL
 
     Kirby Corporation ("Kirby" or the "Company") is primarily a marine
transportation company engaged, through its subsidiaries, in the operation of
vessels on the inland waterway system of the United States and in United States
coastwise and foreign trade. Kirby is also engaged, through subsidiaries, in
diesel repair and property and casualty insurance.
 
     The Company's principal executive offices are located at 1775 St. James
Place, Suite 300, Houston, Texas 77056-3453 and its telephone number is (713)
629-9370. The Company's mailing address is P.O. Box 1745, Houston, Texas
77251-1745.
 
MARINE TRANSPORTATION
 
     The Company's marine transportation business is conducted through three
divisions, organized around the markets they serve: the Inland Chemical
Division, engaged in the inland transportation of industrial chemicals and
agricultural chemicals by tank barges; the Inland Refined Products Division,
engaged in the inland transportation of refined petroleum products by tank
barges; and the Offshore Division, engaged in the offshore transportation of
petroleum products by ocean-going tank barges and tankers and dry bulk,
container and palletized cargo by ocean-going barges and break-bulk and
container ships. The Company's marine transportation divisions are strictly
providers of transportation services and do not assume ownership of any of the
products they transport.
 
   
     The Inland Chemical Division serves industrial chemical companies by
delivering petrochemical feedstocks, processed chemicals, lube oils and
agricultural chemicals to industry users. The Inland Refined Products Division
serves Gulf Coast refineries by transporting gasoline, diesel fuel and jet fuel
to waterfront terminals. Each division operates inland tank barges to
destinations along the Gulf Intracoastal Waterway, the Houston Ship Channel, the
Mississippi River and its tributaries and the Ohio River. As of November 30,
1994, the combined fleet of these divisions consisted of 499 tank barges, 113
towing vessels and seven harbor tugboats.
    
 
   
     The Offshore Division transports petroleum products, dry bulk, container
and palletized cargos, including agricultural commodities, to markets worldwide,
with particular emphasis on ports in the Gulf of Mexico, along the Atlantic
Seaboard, in the Caribbean Basin, South America, West Africa and Europe. As of
November 30, 1994, offshore movements of primarily refined petroleum products
were provided by ten tankers and two ocean-going tank barge and tug units. Dry
bulk cargo movements were provided by six ocean-going barge and tug units and
containers and palletized cargo movements were provided by three break-bulk and
container ships and one ocean-going barge and tug unit.
    
 
DIESEL REPAIR
 
   
     The Company's diesel repair business is engaged in the overhaul and repair
of diesel engines and related parts sales in two distinct markets: the marine
market, serving vessels powered by large diesel engines utilized in the various
inland and offshore marine industries; and the locomotive market, serving the
shortline and industrial railroad markets.
    
 
     The marine market has five service facilities that serve the Gulf Coast,
the East Coast, the Midwest, the West Coast and the Pacific Northwest markets.
Customers in this market include the inland and offshore barge industries,
offshore petroleum and well service industry, offshore commercial fishing
industry and the United States Government.
 
     The locomotive market is served through a facility in Nashville, Tennessee.
As an exclusive distributor for the Electromotive Division of General Motors
Corporation, the locomotive business provides replacement parts, service and
support for locomotives serving shortline and industrial railroads within the
continental United States.
 
                                        3

<PAGE>   5
 
PROPERTY AND CASUALTY INSURANCE
 
     The Company's property and casualty insurance business is engaged in the
writing of property and casualty insurance primarily through Universal Insurance
Company ("Universal") in the Commonwealth of Puerto Rico. A full service
property and casualty insurer, with emphasis on the property lines of business,
Universal is ranked third among Puerto Rico insurance companies in terms of
policyholders' surplus and admitted assets.
 
     On September 25, 1992, Universal merged with Eastern America Insurance
Company ("Eastern America"), a property and casualty insurance company in Puerto
Rico, with Universal being the surviving entity. As of October 25, 1994, the
Company owned approximately 58% of Universal's voting common stock with the
remaining approximately 42% owned by Eastern America Financial Group, Inc.
("Eastern America Group"), the former parent of Eastern America. The Company
owns 100% of the non-voting common and preferred stocks of Universal. In
accordance with a 1992 shareholder agreement among Universal, the Company and
Eastern America Group, through options and redemption rights, Universal has the
right to purchase the Company's interest in Universal over a period of up to 12
years, the result of which would be Eastern America Group becoming the sole
owner of Universal's stock. Since December 1992, the Company has received
$15,000,000 from the redemption by Universal of its capital stock. In August
1994, Eastern America Group purchased additional voting common stock from
Universal for a purchase price of $7,000,000.
 
RECENT DEVELOPMENTS
 
     On July, 1, 1994, the Company purchased a single hull U.S. flag tanker from
Tosco Refining Company. After undergoing extensive capitalized restorations and
modifications, the tanker was placed in service in September 1994 in the
carriage of refined petroleum products in United States coastwise trade and will
operate under a three-year charter. The tanker has a capacity of 266,000 barrels
and a deadweight tonnage of 37,750 and is scheduled to be retired from service
in accordance with the Oil Pollution Act of 1990 ("OPA") on January 1, 1999. The
Company's established bank revolving credit agreement provided funding for the
transaction.
 
   
     On July 21, 1994, the Company purchased three U.S. flag tankers from OMI
Corp. for $23,750,000. The single hull tankers will transport refined petroleum
products primarily between the United States Gulf Coast, Florida and the
mid-Atlantic states. Currently, one of the tankers is operating under a
six-month charter effective October 1994 and one is chartered effective November
1994 for a one year period. The remaining tanker operates in the spot market.
Both of the charters have option periods. Each of the tankers has a total
capacity of 266,000 barrels and a deadweight tonnage of 37,853. In accordance
with the OPA, the three tankers will be retired from service on January 1, 2000.
Funding for the transaction was provided through the Company's established bank
revolving credit agreement.
    
 
     On August 1, 1994, the Board of Directors authorized the Company to
purchase up to 2,000,000 shares of its own common stock. Prior authorization for
the repurchase of the Company common stock was superseded by this authorization.
The Company is authorized to purchase the common stock on the American Stock
Exchange and in privately negotiated transactions. When purchasing common stock,
the Company is subject to price, trading volume and other market considerations.
Shares repurchased may be used for reissuance upon the exercise of stock
options, in future acquisitions for stock or for other appropriate corporate
purposes. To date, the Company has not purchased any common stock under this
authorization.
 
     On August 24, 1994, the Company discontinued its direct, all-water
containership service from central United States (Memphis) to Mexico and Central
America. The service was provided by the Company's wholly owned subsidiary,
Americas Marine Express, Inc. The service was met with aggressive pricing from
its competitors and the prospects for future profitability did not warrant
continuation of the service. Since inception in February 1994, the operation
incurred operating losses and anticipated shut-down expenses of approximately
$2,350,000 ($1,500,000 after taxes or $.05 per share).
 
   
     On November 16, 1994, the Company completed the purchase from The Dow
Chemical Company ("Dow") of 65 inland tank barges, one river towboat and two
shifting boats for approximately $24 million in
    
 
                                        4

<PAGE>   6
 
   
cash. Also, the Company assumed from Dow the lease of an additional 31 inland
tank barges and two towboats. In addition, the Company entered into a contract
with Dow to provide for Dow's inland bulk liquid marine transportation
requirements for a period of ten years. Dow is a major manufacturer of
petrochemicals, industrial chemicals and related bulk liquid products and
historically has used its own barges and outside towing resources to service its
inland marine transportation requirements. Dow produces its products at its
Freeport, Texas manufacturing complex, other plants in Louisiana and at various
other United States locations. A number of the Dow plants, as well as their
suppliers and customers, rely extensively on water transportation for moving
products between Dow's manufacturing facilities, for shipment to the ultimate
users and to move certain raw materials purchased by Dow. Funding for the
transaction was provided through the Company's established bank revolving credit
agreement.
    
 
   
                       RATIO OF EARNINGS TO FIXED CHARGES
    
 
   
     The following table sets forth the ratio of the Company's consolidated
earnings to fixed charges for all periods presented.
    
 
   

<TABLE>
<CAPTION>
                                                    NINE MONTHS
                                                       ENDED
           YEAR ENDED DECEMBER 31,                 SEPTEMBER 30,
- ----------------------------------------------    ----------------
 1993      1992      1991      1990      1989      1994      1993
- ------    ------    ------    ------    ------    ------    ------
<S>       <C>       <C>       <C>       <C>       <C>       <C>
4.70x     2.80x     3.84x     3.86x     3.07x     4.34x     3.19x
</TABLE>

    
 
     For the purpose of computing the ratio of earnings to fixed charges,
"earnings" consists of earnings before taxes on income. "Fixed charges" include
interest expense on debt and one-third of the operating lease expenses, which is
considered to be representative of the interest factor. A statement setting
forth the computation of the ratio of earnings to fixed charges for each of the
periods presented above is filed as an exhibit to the Registration Statement of
which this Prospectus is a part.
 
                                USE OF PROCEEDS
 
     The net proceeds from the sale of the Debt Securities offered hereby will
be used for general corporate purposes, which may include without limitation,
the repayment of indebtedness and funding future acquisitions and working
capital requirements.
 
                         DESCRIPTION OF DEBT SECURITIES
 
     The following description summarizes certain general terms and provisions
of the Debt Securities. The particular terms of the Debt Securities, including
the nature of any variations from the following general provisions, will be
described in the Prospectus Supplement relating to such Debt Securities.
 
   
     The Debt Securities may be issued in one or more series under an Indenture
between the Company and Texas Commerce Bank National Association, as Trustee
(the "Trustee"), dated on or about December 2, 1994 (the "Indenture"). The
Indenture has been filed with the Commission as an exhibit to the Registration
Statement of which this Prospectus constitutes a part and is incorporated by
reference herein.
    
 
     The following summary of certain provisions of the Indenture does not
purport to be complete and is subject to, and is qualified in its entirety by
reference to, all provisions of the Indenture, including the definition therein
of certain terms. All article and section references appearing herein are to
articles and sections of the Indenture. Unless otherwise defined herein, all
capitalized terms shall have the definitions set forth in the Indenture.
 
GENERAL
 
     The Debt Securities to be issued under the Indenture will be unsecured
general obligations of the Company and will rank pari passu with all other
unsecured and unsubordinated indebtedness of the Company from time to time
outstanding. The Debt Securities are currently limited to $250,000,000 aggregate
initial
 
                                        5

<PAGE>   7
 
offering price, or the equivalent thereof in one or more foreign or composite
currencies. The Debt Securities will not be convertible into the common stock or
any other securities of the Company.
 
   
     The Debt Securities are obligations exclusively of the Company, which is a
holding company. Since the operations of the Company are currently conducted
principally through wholly-owned subsidiaries, the cash flow of the Company, and
therefore its ability to service its debt, including the Debt Securities, is
dependent in part upon the earnings of such subsidiaries and the distribution of
those earnings to the Company or upon other payments of funds to the Company by
such subsidiaries. The payment of dividends and the provision of certain loans
and advances to the Company by such subsidiaries may be subject to certain
statutory or contractual restrictions, including financial and other restrictive
covenants contained in agreements relating to indebtedness of the Company or its
subsidiaries.
    
 
   
     In addition, the rights of the Company to participate in any distribution
of assets of any subsidiary upon its liquidation or reorganization or otherwise
(and thus the ability of Holders of the Debt Securities to benefit from such
distribution) are subject to the prior claims of creditors of the subsidiary,
except to the extent that the Company may itself be a creditor with recognized
claims against that subsidiary, and to the prior claims of holders of preferred
stock, if any, issued by the Company's subsidiaries. Claims on the Company's
subsidiaries by creditors may include claims of holders of indebtedness and
claims of creditors in the ordinary course of business, including claims for
trade payables and claims for damages by tort claimants. As of September 30,
1994, the Company's total consolidated indebtedness was approximately $146.3
million, of which approximately $111.8 million consisted of indebtedness of the
Company's subsidiaries. The amount of claims on the Company's subsidiaries by
holders of indebtedness, other creditors and tort claimants may increase or
decrease, and additional claims may be incurred in the future. The Indenture
does not limit the ability of the Company's subsidiaries to incur indebtedness
or issue preferred stock.
    
 
   
     The loan agreement relating to the Company's revolving credit facility
provides that, upon a default under such agreements, the Company will pledge to
the lenders thereunder all of the Company's equity interest in, and all claims
for payment with respect to intercompany indebtedness of, the principal
subsidiaries of the Company. In the event of such a pledge, the rights of the
Company to participate in any distribution of assets of any such subsidiary upon
its liquidation or bankruptcy or otherwise (and thus the ability of Holders of
Debt Securities to benefit from such distribution) would be subject to the prior
claims of such lenders, except to the extent that the Company may itself be a
creditor with other recognized claims against such subsidiary, if any, issued by
such subsidiary.
    
 
   
     The Prospectus Supplement will describe the following terms of the Debt
Securities being offered: (1) the title of the Debt Securities; (2) any limit on
the aggregate principal amount of the Debt Securities; (3) the date or dates on
which the Debt Securities may be issued and the date or dates (or the method of
determination thereof) on which the principal of (and premium, if any, on) the
Debt Securities are or will be payable; (4) the rate or rates (which may be
fixed or variable) at which the Debt Securities will bear interest, if any, or
the method by which such rate or rates shall be determined, the date or dates
from which such interest, if any, will accrue, and the basis on which interest
shall be calculated if other than on the basis of a 360-day year of twelve
30-day months; (5) the date or dates on which such interest, if any, on the Debt
Securities will be payable and the Regular Record Dates for any such Interest
Payment Dates; and the extent to which, or the manner in which, any interest
payable on a global Debt Security ("Global Notes") on an Interest Payment Date
will be paid if other than in the manner described under "Book-Entry System"
below; (6) each office or agency where, subject to the terms of the Indenture as
described below under "Payment and Paying Agents," the principal of, and
premium, if any, and any interest on the Debt Securities will be payable and
each office or agency where, subject to the terms of the Indenture as described
below under "Denominations, Registration and Transfer," the Debt Securities may
be presented for registration of transfer or exchange; (7) the period or periods
within which, the price or prices at which and the terms and conditions upon
which the Debt Securities may be redeemed at the option of the Company; (8) the
obligation, if any, of the Company to redeem, to repay or purchase the Debt
Securities at the option of a Holder thereof and the period or periods within
which, the price or prices at which and the terms and conditions upon which the
Debt Securities will redeemed, repaid or purchased pursuant to any such
obligation; (9) whether the Debt Securities are to be issued with original issue
discount within the meaning of Section 1273(a) of the Internal
    
 
                                        6

<PAGE>   8
 
   
Revenue Code of 1986, as amended (the "Code"), and the regulations thereunder;
(10) whether the Debt Securities are to be issued in whole or in part in the
form of one or more Global Notes and, if so, the identity of the depositary, if
any, for such Global Note or Notes; (11) if other than Dollars, the Foreign
Currency or Currencies or Foreign Currency Units in which the principal of, and
premium, if any, and any interest on the Debt Securities shall or may be paid
and, if applicable, whether at the election of the Company and/or the Holder,
and the conditions and manner of determining the exchange rate or rates; (12)
any index used to determine the amount of payment of principal of and premium,
if any, and any interest on the Debt Securities; (13) any addition to, or
modification or deletion of, any Events of Default or covenants provided for
with respect to the Debt Securities; and (14) any other detailed terms and
provisions of the Debt Securities that are not inconsistent with the Indenture
(Section 301). Any such Prospectus Supplement will also describe any special
provisions for the payment of additional amounts with respect to the Debt
Securities.
    
 
     The Debt Securities may be issued as Discount Securities to be sold at a
substantial discount below their principal amount. "Discount Securities" means
any Debt Securities issued with original issue discount for purposes of the
Code. Special United States income tax and other considerations applicable to
Discount Securities will be described in the Prospectus Supplement relating
thereto. Discount Securities may provide for the declaration or acceleration of
the Maturity of an amount less than the principal amount thereof upon the
occurrence of an Event of Default and the continuation thereof (Sections 101,
502).
 
     The Indenture provides that the Debt Securities may be issued in one or
more series thereunder, in each case as authorized from time to time by the
Board of Directors of the Company. The Indenture also provides that there may be
more than one Trustee under the Indenture, each with respect to one or more
different series of Debt Securities. At a time when two or more Trustees are
acting, each with respect to only certain series, the term "Debt Securities" as
used herein shall mean the one or more series with respect to which each
respective Trustee is acting. In the event there is more than one Trustee under
the Indenture, the powers and trust obligations of each Trustee as described
herein shall extend only to the one or more series of Debt Securities for which
it is Trustee. If more than one Trustee is acting under the Indenture, then the
Debt Securities (whether of one or more than one series) for which each Trustee
is acting shall in effect be treated as if issued under separate indentures.
 
     The Indenture does not contain any provisions that would limit the ability
of the Company to incur indebtedness. Reference is made to the Prospectus
Supplement related to the series of Debt Securities offered thereby for
information with respect to any deletions from, modifications of or additions to
the Events of Default or covenants of the Company applicable to such Debt
Securities that are described herein.
 
     Under the Indenture, the Company will have the ability, in addition to the
ability to issue Debt Securities with terms different from those of Debt
Securities previously issued, without the consent of the Holders, to reopen a
previous issue of a series of Debt Securities and issue additional Debt
Securities of such series, in an aggregate principal amount determined by the
Company.
 
   
     The Company will initially appoint Texas Commerce Bank National Association
to serve as Trustee under the Indenture and Chemical Bank as Paying Agent and
Security Registrar. Texas Commerce Bank National Association, in its capacity as
Trustee, will be responsible for, among other things, transmitting to the
Company any notices or other communications from Holders and transmitting to the
Holders notice of the occurrence of any Event of Default (as defined below) as
soon as practicable after obtaining knowledge thereof. Chemical Bank, in its
capacity as Paying Agent and Security Registrar, will be responsible for, among
other things, maintaining a record of the registration of ownership, exchange
and transfer of the Debt Securities and accepting Debt Securities for exchange
and transfer and ensuring that payments of the principal and premium, if any,
and interest received from the Company in respect of the Debt Securities are
duly paid to the registered Holders thereof.
    
 
DENOMINATIONS, REGISTRATION AND TRANSFER
 
     The Debt Securities of a series may be issuable in whole or in part in the
form of one or more Global Notes, as described below under "Book-Entry System."
Unless otherwise provided in an applicable Prospectus Supplement with respect to
a series of Debt Securities, the Debt Securities will be issuable in fully
registered
 
                                        7

<PAGE>   9
 
form and in denominations of $1,000 or any multiple thereof. One or more Global
Notes will be issued in a denomination or aggregate denominations equal to the
aggregate principal amount of Outstanding Debt Securities of the series to be
represented by such Global Note or Notes (Sections 201, 301, 302, 304).
 
     The Debt Securities of any series (other than a Global Note) will be
exchangeable for other Debt Securities of the same series and of a like
aggregate principal amount and tenor of different authorized denominations. The
Debt Securities may be presented for exchange as provided above, and Debt
Securities (other than a Global Note) may be presented for registration of
transfer (with the form of transfer endorsed thereon duly executed), at the
office of the Security Registrar or co-Security Registrar designated by the
Company for such purpose with respect to any series of Debt Securities and
referred to in an applicable Prospectus Supplement, without service charge and
upon payment of any taxes and other governmental charges as described in the
Indenture. Such transfer or exchange will be effected upon the Security
Registrar or co-Security Registrar being satisfied with the documents of title
and identity of the person making the request.
 
   
PAYMENT AND PAYING AGENTS
    
 
   
     Unless otherwise indicated in an applicable Prospectus Supplement, payment
of principal of, and premium, if any, and any interest on the Debt Securities
will be made at the office of such Paying Agent or Paying Agents as the Company
may designate from time to time. Payment of any interest may be made (i) by
check mailed to the address of the Person entitled thereto as such address shall
appear in the Security Register or (ii) in certain circumstances described in
the applicable Prospectus Supplement, by wire transfer to an account maintained
by the Person entitled thereto (Section 307). Payment of any installment of
interest on the Debt Securities will be made to the Person in whose name such
Debt Security is registered at the close of business on the Regular Record Date
for such interest (Section 307).
    
 
   
     Unless otherwise indicated in an applicable Prospectus Supplement, Chemical
Bank will act as the Company's sole Paying Agent through its office in the
Borough of Manhattan, The City of New York, with respect to the Debt Securities.
Any Paying Agents outside the United States and other Paying Agents in the
United States initially designated by the Company for the Debt Securities being
offered will be named in the accompanying Prospectus Supplement. The Company may
at any time designate additional Paying Agents or rescind the designation of any
Paying Agent or approve a change in the office through which any Paying Agent
acts.
    
 
   
     All moneys paid by the Company to the Trustee or a Paying Agent for the
payment of principal of, and premium, if any, and any interest on any Debt
Securities that remain unclaimed at the end of two years after such principal,
premium or interest shall have become due and payable will, upon request of the
Company as provided in the Indenture, be repaid to the Company, and the Holder
of such Debt Security may thereafter look only to the Company for payment
thereof (Section 1103).
    
 
BOOK-ENTRY SYSTEM
 
     The Debt Securities of a series may be issued in whole or in part in the
form of one or more Global Notes that will be deposited with or on behalf of a
depositary located in the United States (a "Depository") identified in the
Prospectus Supplement relating to such series.
 
     The specific terms of the depositary arrangement with respect to any Debt
Securities of a series will be described in the Prospectus Supplement relating
to such series. The Company anticipates that the following provisions will apply
to all depositary arrangements.
 
     Unless otherwise specified in an applicable Prospectus Supplement, Debt
Securities that are to be represented by a Global Note to be deposited with or
on behalf of a Depositary will be represented by a Global Note registered in the
name of such Depositary or its nominee. Upon the issuance of a Global Note in
registered form, the Depositary for such Global Note will credit on its
book-entry registration and transfer system the respective principal amounts of
the Debt Securities represented by such Global Note to the accounts of
institutions that have accounts with such Depositary or its nominee
("participants"). The
 
                                        8

<PAGE>   10
 
accounts to be credited shall be designated by the underwriters or agents of
such Debt Securities or by the Company, if such Debt Securities are offered and
sold directly by the Company. Ownership of beneficial interests in such Global
Notes will be limited to participants or persons that may hold interests through
participants. Ownership of beneficial interests by participants in such Global
Notes will be shown on, and the transfer of that ownership interest will be
effected only through, records maintained by the Depositary or its nominee for
such Global Note. Ownership of beneficial interests in Global Notes by persons
that hold through participants will be shown on, and the transfer of that
ownership interest within such participant will be effected only through,
records maintained by such participant. The laws of some jurisdictions require
that certain purchasers of securities take physical delivery and such securities
in definitive form. Such limits and such laws may impair the ability to transfer
beneficial interests in a Global Note.
 
   
     So long as the Depositary for a Global Note, or its nominee, is the
registered owner of such Global Note, the Depositary or its nominee, as the case
may be, will be the sole Holder of the Global Notes represented thereby for all
purposes under the Indenture. Except as otherwise provided in this section, the
beneficial owners of such Global Notes will not be entitled to receive physical
delivery of Certificated Notes and will not be considered the Holders thereof
for any purpose under the Indenture, and no Global Notes shall be exchangeable
or transferrable by the owners of beneficial interests. Accordingly, each person
owning a beneficial interest in a Global Note must rely on the procedures of the
Depositary and, if such person is not a participant, on the procedures of the
participant through which such person owns its interest in order to exercise any
rights of a Holder under the Indenture.
    
 
     Payment of principal of, premium, if any, and any interest on Debt
Securities registered in the name of or held by a Depositary or its nominee will
be made to the Depositary or its nominee, as the case may be, as the registered
owner or the holder of the Global Note representing such Debt Securities. None
of the Company, the Trustee, any Paying Agent or the Security Registrar for such
Debt Securities will have any responsibility or liability for any aspect of the
records relating to or payments made on account of beneficial ownership
interests in a Global Note for such Debt Securities or for maintaining,
supervising or reviewing any records relating to such beneficial ownership
interests.
 
     The Company expects that the Depositary for Debt Securities of a series,
upon receipt of any payment of principal, premium or interest in respect of a
permanent Global Note, will credit immediately participants' accounts with
payments in amounts proportionate to their respective beneficial interests in
the principal amount of such Global Note as shown on the records of such
Depositary. The Company also expects that payments will be governed by standing
instructions and customary practices, as is now the case with the securities
held for the accounts of customers registered in "street name," and will be the
responsibility of such participants and not the Company.
 
   
     A Global Note may not be transferred except as a whole by the Depositary
for such Global Note to a nominee of such Depositary or by a nominee of such
Depositary to such Depositary or another nominee of such Depositary or by such
Depositary or any such nominee to a successor of such Depositary or a nominee of
such successor (Section 304). If a Depositary for Debt Securities of a series is
at any time unwilling or unable to continue as Depositary or ceases to be a
clearing agency registered under the Exchange Act and a successor Depositary is
not appointed by the Company within 90 days after the Company receives notice
from the Depositary or otherwise becomes aware of such condition or if there
shall have occurred and be continuing an Event of Default under the Indenture
with respect to the series of Debt Securities, the Company will issue Debt
Securities in definitive registered form in exchange for the Global Note or
Notes representing such Debt Securities. In addition, the Company may at any
time and in its sole discretion determine not to have any Debt Securities
represented by one or more Global Notes and, in such event, will issue Debt
Securities in definitive registered form in exchange for all the Global Notes
representing such Debt Securities. In any such instance, an owner of a
beneficial interest in a Global Note will be entitled to physical delivery in
definitive form of Debt Securities of the series represented by such Global Note
equal in principal amount to such beneficial interest and to have such Debt
Securities registered in its name.
    
 
                                        9

<PAGE>   11
 
COVENANTS
 
   
     The Indenture requires the Company to maintain its corporate existence and
maintain an office or agency where Debt Securities may be presented or
surrendered for payment, transfer or exchange.
    
 
   
     The Indenture does not contain any financial performance covenants.
Consequently, the Company is not required under the Indenture to meet any
financial tests such as those that measure the Company's working capital,
interest coverage, fixed charge coverage, amount of indebtedness or net worth in
order to maintain compliance with the terms of the Indenture.
    
 
EVENTS OF DEFAULT
 
   
     The following are Events of Default under the Indenture with respect to the
Debt Securities: (a) failure to pay principal of or any premium on any Debt
Security of that series when due; (b) failure to pay any interest on any Debt
Security of that series when due, continued for 30 days; (c) failure to perform
any other covenant of the Company in the Indenture (other than a covenant
included in the Indenture solely for the benefit of a series of Debt Securities
other than the series), continued for 60 days after written notice as provided
in the Indenture; (d) certain events in bankruptcy, insolvency or
reorganization; (e) failure to pay indebtedness for borrowed money of the
Company or any Significant Subsidiary aggregating in excess of $5,000,000,
continued for 30 days; and (f) any other Event of Default provided with respect
to Debt Securities of that series (Section 501). If any Event of Default, other
than bankruptcy, insolvency and reorganization Events of Default, with respect
to Debt Securities of any series at any time Outstanding occurs and is
continuing, either the Trustee or the Holders of at least 25% in aggregate
principal amount of the Outstanding Debt Securities of that series may declare
the principal amount (or, if the Debt Securities of that series are Discount
Securities, such portion of the principal amount as may be specified in the
terms of that series) of all the Debt Securities of that series to be due and
payable immediately. If any bankruptcy, insolvency or reorganization Event of
Default provided with respect to Debt Securities of any series at any time
Outstanding occurs and is continuing, the principal amount (or, if such the Debt
Securities of that series are Discount Securities, such portion of the principal
amount as may be specified in the terms of that series) of all the Debt
Securities of that series shall be immediately due and payable without any
declaration, notice or act of the Trustee or any Holder. At any time after a
declaration of acceleration with respect to Debt Securities of any series has
been made, but before a judgment or decree based on acceleration has been
obtained, the Holders of a majority in aggregate principal amount of Outstanding
Debt Securities of that series may, under certain circumstances, rescind and
annul such acceleration (Section 502).
    
 
   
     The Indenture provides that, subject to the duty of the Trustee during
default to act with the required standard of care, the Trustee will be under no
obligation to exercise any of its rights or powers under the Indenture at the
request or direction of any of the Holders, unless such Holders shall have
offered to the Trustee reasonable indemnity (Section 603). Subject to such
provisions for the indemnification of the Trustee and certain time limits which
may be imposed by the Company pursuant to the terms of the Indenture, the
Holders of a majority in aggregate principal amount of the Outstanding Debt
Securities of any series will have the right to direct the time, method and
place of conducting any proceeding for any remedy available to the Trustee, or
exercising any trust or power conferred on the Trustee, with respect to the Debt
Securities of that series (Sections 512, 701).
    
 
   
     The Company is required to furnish the Trustee annually with a statement as
to the performance by the Company of certain of its obligations under the
Indenture and as to any default in such performance (Section 1105).
    
 
MODIFICATION AND WAIVER
 
     Modifications of and amendments to the Indenture may be made by the Company
and the Trustee with the consent of the Holders of not less than a majority in
aggregate principal amount of the Outstanding Debt Securities of each series
affected by such modification or amendment; provided, however, that no such
modification or amendment may without the consent of the Holder of each
Outstanding Debt Security affected thereby, (a) change the Stated Maturity of
the principal of, or any installment of interest, if any, on,
 
                                       10

<PAGE>   12
 
   
any Debt Security, (b) reduce the principal amount of, or any premium or
interest on, any Debt Security, (c) reduce the amount of principal of Discount
Debt Securities payable upon acceleration of the maturity thereof, (d) change
the currency payment of principal of, or any premium or interest on, any Debt
Security, (e) adversely affect the right of repayment or repurchase, if any, at
the option of the Holder, (f) impair the right to institute suit for the
enforcement of any payment on or with respect to any Debt Security, (g) certain
modifications to Sections 513, 1002 and 1105 of the Indenture, or (h) reduce the
percentage in principal amount of Outstanding Debt Securities of any series, the
consent of whose Holders is required for modification or amendment of the
Indenture or for waiver of compliance with certain provisions of the Indenture
or for waiver of certain defaults (Section 1002).
    
 
     The Holders of a majority in aggregate principal amount of the Outstanding
Debt Securities of each series may, on behalf of all Holders of Debt Securities
of that series, waive any past default under the Indenture with respect to Debt
Securities of that series, except (i) a default in the payment of principal or
any premium or interest or (ii) a covenant or provision that cannot be modified
or amended without the consent of the Holders of each Outstanding Debt Security
affected thereby (Section 513).
 
CONSOLIDATION, MERGER, SALE OR LEASE OF ASSETS
 
   
     The Company shall not, without the consent of the Holders of the
Outstanding Debt Securities under the Indenture, consolidate with or merge into,
or transfer or lease its assets substantially as an entirety to any Person
unless (i) the successor Person is a corporation organized under the laws of any
domestic jurisdiction, (ii) the successor corporation assumes the Company's
obligations on the Debt Securities and under the Indenture, (iii) immediately
after giving effect to the transactions no Event of Default, and no event which,
after notice or lapse of time, or both, would become an Event of Default, shall
have occurred and be continuing, and (iv) certain other conditions are met
(Section 901).
    
 
DEFEASANCE
 
   
     If so specified in the Prospectus Supplement with respect to Debt
Securities of any series, the Company will be discharged from any and all
obligations in respect of the Debt Securities of such series (except for certain
obligations to register the transfer or exchange of Debt Securities of such
series, replace stolen, lost or mutilated Debt Securities of such series,
maintain paying agencies and hold moneys for payment in trust) if the Company
deposits with the Trustee, in trust, money or U.S. Government Obligations (as
defined in the indenture) which through the payment of interest thereon and
principal thereof in accordance with their terms will provide money in an amount
sufficient to pay all the principal, premium, if any, and interest on the Debt
Securities of such series on the dates such payments are due in accordance with
the terms of such Debt Securities. To exercise any such option, the Company is
required, among other things, to deliver to the Trustee an opinion of counsel to
the effect that (1) the deposit, related defeasance and, if applicable,
discharge would not cause the Holders of the Debt Securities of such series to
recognize income, gain or loss for United States income tax purposes and will be
subject to federal income tax on the same amount, in the same manner and at the
same times as would have been the case if such deposit, defeasance and, if
applicable, discharge had not occurred and (2) if the Debt Securities of such
series are then listed on any national securities exchange, such Debt Securities
would not be delisted from such exchange as a result of the exercise of such
option (Article Thirteen).
    
 
NOTICES
 
     Notices to Holders will be given by mail to the addresses of such Holders
as they appear in the Security Register (Section 105).
 
GOVERNING LAW
 
     The Indenture and the Debt Securities will be governed by, and construed in
accordance with, the laws of the State of New York (Section 111).
 
CONCERNING THE TRUSTEE
 
     The Trustee has normal banking relationships with the Company.
 
                                       11

<PAGE>   13
 
                              PLAN OF DISTRIBUTION
 
GENERAL
 
     The Company may sell Debt Securities to or through underwriters or a group
of underwriters, directly to other purchasers, or through dealers or agents. The
distribution of the Debt Securities may be effected from time to time in one or
more transactions at a fixed price or prices, which may be changed, at market
prices prevailing at the time of sale, at prices related to such prevailing
market prices or at negotiated prices. Each Prospectus Supplement will describe
the method of distribution, and time and place of delivery, of the offered Debt
Securities. The Company also may, from time to time, authorize dealers, acting
as the Company's agents, to solicit offers to purchase the offered Debt
Securities upon the terms and conditions set forth in any Prospectus Supplement.
 
     In connection with the sale of Debt Securities, underwriters, dealers or
agents may receive compensation from the Company or from purchasers of Debt
Securities for whom they may act as agents, in the form of discounts,
concessions or commissions. Underwriters, dealers and agents that participate in
the distribution of Debt Securities may be deemed to be "underwriters," and any
discounts or commissions received by them and any profit on the resale of Debt
Securities by them may be deemed to be underwriting discounts and commissions,
under the Securities Act. Any such underwriter, dealer or agent will be
identified, and any such compensation will be described, in the Prospectus
Supplement relating to the offered Debt Securities.
 
     Under agreements that may be entered into by the Company, underwriters,
dealers and agents that participate in the distribution of Debt Securities may
be entitled to indemnification by the Company against certain liabilities,
including liabilities under the Securities Act.
 
     Each issuance of a series of Debt Securities will constitute a new issue of
securities with no established trading market. In the event that Debt Securities
of a series offered hereunder are not listed on a national securities exchange,
certain broker-dealers may make a market in the Debt Securities, but will not be
obligated to do so and may discontinue any market making at any time without
notice. No assurance can be given that any broker-dealer will make a market in
the Debt Securities of any series or as to the liquidity of the trading market
for such Debt Securities.
 
DELAYED DELIVERY ARRANGEMENT
 
     If so indicated in the Prospectus Supplement relating to offered Debt
Securities, the Company will authorize dealers or other persons acting as the
Company's agents to solicit offers by certain institutions to purchase Debt
Securities from the Company pursuant to contracts providing for payment and
delivery on a future date. Institutions with which such contracts may be made
include commercial and savings banks, insurance companies, pension funds,
investment companies, educational and charitable institutions and others, but in
all cases such institutions must be approved by the Company. The obligations of
any purchaser under any such contract will be subject to the condition that the
purchase of Debt Securities shall not at the time of delivery be prohibited
under the laws of the jurisdiction to which such purchaser is subject. The
dealers and such other agents will not have any responsibility in respect of the
validity or performance of such contracts.
 
                                 LEGAL OPINIONS
 
   
     Certain matters with respect to the validity of the Debt Securities offered
hereby will be passed upon for the Company by Jenkens & Gilchrist, a
Professional Corporation, Dallas, Texas, and for any underwriters, dealers or
agents, as the case may be, by Andrews & Kurth L.L.P., Houston, Texas. Henry
Gilchrist, the Secretary and an Advisory Director of the Company, is a
shareholder of Jenkens & Gilchrist, a Professional Corporation. Jenkens &
Gilchrist, a Professional Corporation will rely on Andrews & Kurth L.L.P. as to
matters of New York law.
    
 
                                       12

<PAGE>   14
 
                                    EXPERTS
 
     The financial statements and schedules of the Company and consolidated
subsidiaries as of December 31, 1992 and 1993 and for the years then ended,
incorporated by reference in this Prospectus, have been incorporated by
reference herein in reliance upon the reports of KPMG Peat Marwick LLP and
Deloitte & Touche LLP, independent auditors, incorporated by reference herein,
and upon the authority of said firms as experts in accounting and auditing. The
reports of KPMG Peat Marwick LLP refer to changes in the methods of accounting
for income taxes, postretirement benefits other than pensions, certain
investments in debt and equity securities and accounting and reporting for
reinsurance of short-duration and long-duration contracts.
 
     The financial statements and schedules of the Company and consolidated
subsidiaries as of December 31, 1991 and for the year then ended, incorporated
by reference in this Prospectus, have been incorporated by reference herein in
reliance upon the report of Deloitte & Touche LLP, independent auditors,
incorporated by reference herein, and upon the authority of said firm as experts
in accounting and auditing.
 
                                       13

<PAGE>   15
 

                                    PART II
 
                   INFORMATION NOT REQUIRED IN THE PROSPECTUS
 
ITEM 14.  OTHER EXPENSES OF ISSUANCE AND DISTRIBUTION.
 
     Expenses payable in connection with the distribution of the securities
being registered (estimated except for the registration fee, substantially all
of which will be borne by the Company, are as follows:
 

<TABLE>
    <S>                                                                         <C>
    Registration fee..........................................................  $ 86,207
    Printing and engraving expenses...........................................    25,000*
    Legal fees and expenses...................................................    50,000*
    Accounting fees and expenses..............................................    25,000*
    Fees and expenses of Trustee..............................................    15,000*
    Blue sky fees and expenses................................................    10,000*
    Rating Agency fees........................................................   135,000*
    Miscellaneous expenses....................................................    13,793*
    Total.....................................................................  $360,000*
</TABLE>

 
- ---------------
 
* Estimated
 
ITEM 15.  INDEMNIFICATION OF DIRECTORS AND OFFICERS.
 
     (a) The Restated Articles of Incorporation of the Company provide for
indemnification as follows:
 
          "TWELFTH: 1. The corporation shall indemnify any person who was or is
     a party or is threatened to be made a party to any threatened, pending or
     completed action, suit or proceeding, whether civil, criminal,
     administrative or investigative, except an action by or in the right of the
     corporation, by reason of the fact that he is or was a director, officer,
     employee or agent of the corporation, or is or was serving at the request
     of the corporation as a director, officer, employee or agent of another
     corporation, partnership, joint venture, trust or other enterprise, against
     expenses, including attorneys' fees, judgments, fines and amounts paid in
     settlement actually and reasonably incurred by him in connection with the
     action, suit or proceeding if he acted in good faith and in a manner which
     he reasonably believed to be in or not opposed to the best interests of the
     corporation, and, with respect to any criminal action or proceeding, has no
     reasonable cause to believe his conduct was unlawful. The termination of
     any action, suit or proceeding by judgment, order, settlement, conviction,
     or upon a plea of nolo contendere or its equivalent, does not, of itself,
     create a presumption that the person did not act in good faith and in a
     manner which he reasonably believed to be in or not opposed to the best
     interests of the corporation, and that, with respect to any criminal action
     or proceeding, he had reasonable cause to believe that his conduct was
     unlawful.
 
          2. The corporation shall indemnify any person who was or is a party or
     is threatened to be made a party to any threatened, pending or completed
     action or suit by or in the right of the corporation to procure a judgment
     in its favor by reason of the fact that he is or was a director, officer,
     employee or agent of the corporation, or is or was serving at the request
     of the corporation as a director, officer, employee or agent of another
     corporation, partnership, joint venture, trust or other enterprise against
     expenses, including amounts paid in settlement and attorneys' fees actually
     and reasonably incurred by him in connection with the defense or settlement
     of the action or suit if he acted in good faith and in a manner which he
     reasonably believed to be in or not opposed to the best interests of the
     corporation. Indemnification shall not be made for any claim, issue or
     matter as to which such a person has been adjudged by a court of competent
     jurisdiction, after exhaustion of all appeals therefrom, to be liable to
     the corporation or for amounts paid in settlement to the corporation unless
     and only to the extent that the court in which the action or suit was
     brought or other court of competent jurisdiction determines upon
     application that in view of all the circumstances of the case, the person
     is fairly and reasonably entitled to indemnity for such expenses as the
     court deems proper.
 
                                      II-1

<PAGE>   16
 
          3. To the extent that a director, officer, employee or agent of a
     corporation has been successful on the merits or otherwise in defense of
     any action, suit or proceeding referred to in sections 1 and 2 of this
     Article Twelfth, or in defense of any claim, issue or matter therein, he
     must be indemnified by the corporation against expenses, including
     attorneys' fees, actually and reasonably incurred by him in connection with
     the defense.
 
          4. Any indemnification under sections 1 and 2 of this Article Twelfth,
     unless ordered by a court or advanced pursuant to section 5 of this Article
     Twelfth, must be made by the corporation only as authorized in the specific
     case upon a determination that indemnification of the director, officer,
     employee or agent is proper in the circumstances. The determination must be
     made:
 
             (a) By the stockholders;
 
             (b) By the board of directors by majority vote of a quorum
        consisting of directors who were not parties to the act, suit or
        proceeding;
 
             (c) If a majority vote of a quorum consisting of directors who were
        not parties to the act, suit or proceeding so orders, by independent
        legal counsel in a written opinion; or
 
             (d) If a quorum consisting of directors who were not parties to the
        act, suit or proceeding cannot be obtained, by independent legal counsel
        in a written opinion.
 
          5. The expenses of officers and directors incurred in defending a
     civil or criminal action, suit or proceeding must be paid by the
     corporation as they are incurred and in advance of the final disposition of
     the action, suit or proceeding upon receipt of an undertaking by or on
     behalf of the director or officer to repay the amount if it is ultimately
     determined by a court of competent jurisdiction that he is not entitled to
     be indemnified by the corporation. The provisions of this section 5 of this
     Article Twelfth do not affect any rights to advancement of expenses to
     which corporate personnel other than directors or officers may be entitled
     under any contract or otherwise by law.
 
          6. The indemnification and advancement of expenses provided by this
     Article Twelfth:
 
             (a) Does not exclude any other rights to which a person seeking
        indemnification or advancement of expenses may be entitled under these
        articles of incorporation or any bylaws, agreement, vote of stockholders
        or disinterested directors or otherwise, for either an action in his
        official capacity or an action in another capacity while holding his
        office, except that indemnification, unless ordered by a court pursuant
        to section 2 of this Article Twelfth or for the advancement of expenses
        of any director or officer, if a final adjudication establishes that his
        acts or omissions involved intentional misconduct, fraud or a knowing
        violation of the law and was material to the cause of action.
 
             (b) Continues for a person who has ceased to be a director,
        officer, employee or agent and inures to the benefit of the heirs,
        executors and administrators of such a person.
 
          7. The corporation may purchase and maintain insurance or make other
     financial arrangements on behalf of any person who is or was a director,
     officer, employee or agent of the corporation, or is or was serving at the
     request of the corporation as a director, officer, employee or agent of
     another corporation, partnership, joint venture, trust or other enterprise
     for any liability asserted against him and liability and expenses incurred
     by him in his capacity as a director, officer, employee or agent, or
     arising out of his status as such, whether or not the corporation has the
     authority to indemnify him against such liability and expenses.
 
          8. The other financial arrangements made by the corporation pursuant
     to section 7 of this Article Twelfth may include the following:
 
             (a) The creation of a trust fund.
 
             (b) The establishment of a program of self-insurance.
 
             (c) The securing of its obligation of indemnification by granting a
        security interest or other lien on any assets of the corporation.
 
             (d) The establishment of a letter of credit, guaranty or surety.
 
                                      II-2

<PAGE>   17
 
     No financial arrangement made pursuant to this section may provide
     protection for a person adjudged by a court of competent jurisdiction,
     after exhaustion of all appeals therefrom, to be liable for intentional
     misconduct, fraud or a knowing violation of law, except with respect to the
     advancement of expenses or indemnification ordered by a court.
 
          9. Any insurance or other financial arrangement made on behalf of a
     person pursuant to this Article Twelfth may be provided by the corporation
     or any other person approved by the board of directors, even if all or part
     of the other person's stock or other securities is owned by the
     corporation.
 
          10. In the absence of fraud:
 
             (a) The decision of the board of directors as to the propriety of
        the terms and conditions of any insurance or other financial arrangement
        made pursuant to this Article Twelfth and the choice of the person to
        provide the insurance or other financial arrangement shall be
        conclusive; and
 
             (b) The insurance or other financial arrangement:
 
                (1) Is not void or voidable; and
 
                (2) Does not subject any director approving it to personal
           liability for his action, even if a director approving the insurance
           or other financial arrangement is a beneficiary of the insurance or
           other financial arrangement."
 
     (b) The Company has entered into agreements with each Director, certain key
employees, including Brian K. Harrington and G. Stephen Holcomb, and certain
directors of subsidiaries of the Company, that provide for the indemnification
of such individuals for certain liabilities incurred in such capacity.
 
     See "Undertakings" (Item 17), for an understanding by the Company relating
to claims for indemnification, pursuant to these provisions, in connection with
the securities being registered.
 
ITEM 16.  EXHIBITS
 
   

<TABLE>
<S>                  <C>
          4.1        -- Restated Articles of Incorporation of the Company, as amended
                        (incorporated by reference to Exhibit 3.1 of the Registrant's 1989
                        Registration Statement on Form S-3 (Reg. No. 33-30832)).
          4.2        -- Certificate of Amendment of Restated Articles of Incorporation of the
                        Company filed with the Secretary of state of Nevada April 30, 1990
                        (incorporated by reference to Exhibit 3.2 of Registrant's Annual
                        Report on Form 10-K for the year ended December 31, 1991).
          4.3        -- Form of Indenture between the Company and Texas Commerce Bank
                        National Association, as Trustee (included in this Part II).
          5.1        -- Opinion of Jenkens & Gilchrist, a Professional Corporation, counsel
                        for the Company, as to the validity of the Debt Securities (included
                        in this Part II).
         12.1        -- Statement regarding computation of ratio of earnings to fixed charges
                        (previously filed).
         23.1        -- Consent of Jenkens & Gilchrist, a Professional Corporation (included
                        in the Opinion in Exhibit 5.1).
         23.2        -- Consent of KPMG Peat Marwick LLP (previously filed).
         23.3        -- Consent of Deloitte & Touche LLP (previously filed).
         24.1        -- Power of Attorney of certain officers and directors (included in this
                        Part II).
         25.1        -- Statement of Eligibility of Trustee on Form T-1 (previously filed).
</TABLE>

    
 
                                      II-3

<PAGE>   18
 
ITEM 17.  UNDERTAKINGS.
 
     Insofar as indemnification for liabilities arising under the Securities Act
of 1933 may be permitted to directors, officers and controlling persons of the
Registrant pursuant to the foregoing provisions, or otherwise, the Registrant
has been advised that in the opinion of the Securities and Exchange Commission
such indemnification is against public policy as expressed in the Act and is,
therefore, unenforceable. In the event a claim for indemnification against such
liabilities (other than the payment by the Registrant of expenses incurred or
paid by a director, officer or controlling person of the Registrant in the
successful defense of any action, suit or proceeding) is asserted by such
director, officer or controlling person in connection with the securities being
registered, the Registrant will, unless in the opinion of its counsel the matter
has been settled by controlling precedent, submit to a court of appropriate
jurisdiction the question whether such indemnification by it is against public
policy as expressed in the Act and will be governed by the final adjudication of
such issue.
 
     The undersigned Registrant hereby undertakes that:
 
          (1) For purposes of determining any liability under the Securities Act
     of 1933, the information omitted from the form of Prospectus filed as part
     of this Registration Statement in reliance upon Rule 430A and contained a
     form of Prospectus filed by the Registrant pursuant to Rule 424(b)(1) or
     (4) or 497(h) under the Securities Act shall be deemed to be part of this
     Registration Statement as of the time it was declared effective.
 
          (2) For the purpose of determining any liability under the Securities
     Act of 1933, each post-effective amendment that contains a form of
     Prospectus shall be deemed to be a new registration statement relating to
     the securities offered therein, and the offering of such securities at that
     time shall be deemed to be the initial bona fide offering thereof.
 
     The undersigned Registrant hereby undertakes that for purposes of
determining any liability under the Securities Act of 1933, each filing of the
Registrant's annual report pursuant to Section 13(a) or Section 15(d) of the
Securities Exchange Act of 1934 that is incorporated by reference in this
Registration Statement shall be deemed to be a new registration statement
relating to the securities offered herein, and the offering of such securities
at that time shall be deemed to be the initial bona fide offering thereof.
 
                                      II-4

<PAGE>   19
 

                                   SIGNATURES
 
   
     PURSUANT TO THE REQUIREMENTS OF THE SECURITIES ACT OF 1933, THE REGISTRANT
CERTIFIES THAT IT HAS REASONABLE GROUNDS TO BELIEVE THAT IT MEETS ALL OF THE
REQUIREMENTS FOR FILING ON FORM S-3 AND HAS DULY CAUSED THIS REGISTRATION
STATEMENT TO BE SIGNED ON ITS BEHALF BY THE UNDERSIGNED, THEREUNTO DULY
AUTHORIZED, IN THE CITY OF HOUSTON, STATE OF TEXAS, ON DECEMBER 1, 1994.
    
 
                                            KIRBY CORPORATION
 
                                            By:   /s/  GEORGE A. PETERKIN, JR.
                                                    George A. Peterkin, Jr.
                                                           President
 
                               POWER OF ATTORNEY
 
     KNOW ALL MEN BY THESE PRESENTS, that each person whose signature appears
below hereby constitutes and appoints George A. Peterkin, Jr. and Brian K.
Harrington, and each of them, his true and lawful attorneys-in-fact and agents,
with full power of substitution and resubstitution, for him and in his name,
place and stead, in any and all capacities, to sign any and all amendments
(including post-effective amendments) to this registration statement, and to
file the same, with all exhibits thereto, and other documents in connection
therewith, with the Securities and Exchange Commission, granting unto said
attorneys-in-fact and agents full power and authority to do and perform each and
every act and thing requisite and necessary to be done, as fully to all intents
and purposes as he might or could do in person, hereby ratifying and confirming
all that said attorneys-in-fact and agents or their or his substitute or
substitutes, may lawfully do or cause to be done by virtue hereof.
 
     PURSUANT TO THE REQUIREMENTS OF THE SECURITIES ACT OF 1933, THIS
REGISTRATION STATEMENT HAS BEEN SIGNED BY THE FOLLOWING PERSONS IN THE
CAPACITIES AND ON THE DATES INDICATED.
 
   

<TABLE>
<CAPTION>
                  SIGNATURE                             CAPACITY                    DATE
- ---------------------------------------------  ---------------------------   ------------------
<S>                                            <C>                           <C>
 
             /s/  ROBERT G. STONE, JR.         Chairman of the Board and       December 1, 1994
              (Robert G. Stone, Jr.)             Director of the Company
 
           /s/  GEORGE A. PETERKIN, JR.        President and Director of       December 1, 1994
            (George A. Peterkin, Jr.)            the Company (Principal
                                                 Executive Officer)
 
                 /s/  J. H. PYNE                Executive Vice President        December 1, 1994
                  (J. H. Pyne)                   and Director of the
                                                 Company


           /s/  BRIAN K. HARRINGTON            Senior Vice President,          December 1, 1994
            (Brian K. Harrington)                Treasurer, Assistant
                                                 Secretary of the Company
                                                 (Principal Financial
                                                 Officer)
 
            /s/  G. STEPHEN HOLCOMB            Vice President, Controller,     December 1, 1994
             (G. Stephen Holcomb)                Assistant Treasurer,
                                                 Assistant Secretary of
                                                 the Company (Principal
                                                 Accounting Officer)
</TABLE>

    
 
                                      II-5

<PAGE>   20
 
   

<TABLE>
<CAPTION>
                  SIGNATURE                             CAPACITY                    DATE
- ---------------------------------------------  ---------------------------   ------------------
<S>                                            <C>                           <C>
          /s/  GEORGE F. CLEMENTS, JR.         Director of the Company         December 1, 1994
           (George F. Clements, Jr.)
 
            /s/  J. PETER KLEIFGEN             Director of the Company         December 1, 1994
             (J. Peter Kleifgen)
 
         /s/  WILLIAM M. LAMONT, JR.           Director of the Company         December 1, 1994
          (William M. Lamont, Jr.)
 
          /s/  C. W. MURCHISON, III            Director of the Company         December 1, 1994
           (C. W. Murchison, III)
 
           /s/  J. VIRGIL WAGGONER             Director of the Company         December 1, 1994
            (J. Virgil Waggoner)
</TABLE>

    
 
                                      II-6

<PAGE>   21


                                 EXHIBIT INDEX

<TABLE>
<S>                  <C>
          4.1        -- Restated Articles of Incorporation of the Company, as amended 
                        (incorporated by reference to Exhibit 3.1 of the Registrant's 1989
                        Registration Statement on Form S-3 (Reg. No. 33-30832)).
          4.2        -- Certificate of Amendment of Restated Articles of Incorporation of the
                        Company filed with the Secretary of state of Nevada April 30, 1990
                        (incorporated by reference to Exhibit 3.2 of Registrant's Annual
                        Report on Form 10-K for the year ended December 31, 1991).
          4.3        -- Form of Indenture between the Company and Texas Commerce Bank
                        National Association, as Trustee (included in this Part II).
          5.1        -- Opinion of Jenkens & Gilchrist, a Professional Corporation, counsel
                        for the Company, as to the validity of the Debt Securities (included
                        in this Part II).
         12.1        -- Statement regarding computation of ratio of earnings to fixed charges
                        (previously filed).
         23.1        -- Consent of Jenkens & Gilchrist, a Professional Corporation (included
                        in the Opinion in Exhibit 5.1).
         23.2        -- Consent of KPMG Peat Marwick LLP (previously filed).
         23.3        -- Consent of Deloitte & Touche LLP (previously filed).
         24.1        -- Power of Attorney of certain officers and directors (included in this
                        Part II).
         25.1        -- Statement of Eligibility of Trustee on Form T-1 (previously filed).
</TABLE>








<PAGE>   1


================================================================================



                               KIRBY CORPORATION



                                       TO



                    TEXAS COMMERCE BANK NATIONAL ASSOCIATION
                                    TRUSTEE



                    ========================================




                                   INDENTURE



                         DATED AS OF DECEMBER 2, 1994



                    ========================================



                                DEBT SECURITIES





================================================================================

<PAGE>   2
                               TABLE OF CONTENTS



<TABLE>
<CAPTION>
                                                                                                                       Page
                                                                                                                       ----
<S>                                                                                                                     <C>
ARTICLE ONE

DEFINITIONS AND OTHER PROVISIONS OF GENERAL APPLICATION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .    1
         SECTION 101.  Definitions. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .    1
         SECTION 102.  Compliance Certificates and Opinions.  . . . . . . . . . . . . . . . . . . . . . . . . . . . .   10
         SECTION 103.  Form of Documents Delivered to Trustee.  . . . . . . . . . . . . . . . . . . . . . . . . . . .   10
         SECTION 104.  Notices, etc., to Trustee and Company. . . . . . . . . . . . . . . . . . . . . . . . . . . . .   11
         SECTION 105.  Notice to Holders; Waiver. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .   11
         SECTION 106.  Conflict with Trust Indenture Act. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .   12
         SECTION 107.  Effect of Headings and Table of Contents.  . . . . . . . . . . . . . . . . . . . . . . . . . .   12
         SECTION 108.  Successors and Assigns.  . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .   12
         SECTION 109.  Separability Clause. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .   12
         SECTION 110.  Benefits of Indenture. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .   12
         SECTION 111.  Governing Law. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .   12
         SECTION 112.  Legal Holidays.  . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .   13
         SECTION 113.  No Security Interest Created.  . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .   13
         SECTION 114.  Liability Solely Corporate.  . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .   13
         SECTION 115.  Interest Limitation  . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .   14
         SECTION 116.  Counterparts.  . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .   15

ARTICLE TWO

DEBT SECURITY FORMS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .   15
         SECTION 201.  Forms Generally. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .   15
         SECTION 202.  Form of Trustee's Certificate of Authentication. . . . . . . . . . . . . . . . . . . . . . . .   15

ARTICLE THREE

THE DEBT SECURITIES . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .   17
         SECTION 301.  Amount Unlimited; Issuable in Series.  . . . . . . . . . . . . . . . . . . . . . . . . . . . .   17
         SECTION 302.  Denominations. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .   20
         SECTION 303.  Execution, Authentication, Delivery and
 Dating.  . . . . . . . . . . . . . . . . . . . . . . .   20
         SECTION 304.  Temporary Debt Securities; Global Notes. . . . . . . . . . . . . . . . . . . . . . . . . . . .   22
         SECTION 305.  Registration, Transfer and Exchange. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .   24
         SECTION 306.  Mutilated, Destroyed, Lost and Stolen Debt Securities  . . . . . . . . . . . . . . . . . . . .   25
         SECTION 307.  Payment of Interest; Interest Rights Preserved.  . . . . . . . . . . . . . . . . . . . . . . .   26
         SECTION 308.  Cancellation.  . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .   27
         SECTION 309.  Computation of Interest. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .   27
         SECTION 310.  Currency of Payments In Respect of Debt Securities.  . . . . . . . . . . . . . . . . . . . . .   27
         SECTION 311.  Judgments. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .   31
</TABLE>






                                       i

<PAGE>   3

<TABLE>
<S>                                                                                                                     <C>
ARTICLE FOUR

SATISFACTION AND DISCHARGE  . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .   31
         SECTION 401.  Satisfaction and Discharge of Indenture. . . . . . . . . . . . . . . . . . . . . . . . . . . .   31
         SECTION 402.  Application of Trust Money.  . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .   33

ARTICLE FIVE

REMEDIES  . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .   33
         SECTION 501.  Events of Default. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .   33
         SECTION 502.  Acceleration of Maturity; Rescission and Annulment.  . . . . . . . . . . . . . . . . . . . . .   35
         SECTION 503.  Collection of Indebtedness and Suits for Enforcement by
                        Trustee.  . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .   36
         SECTION 504.  Trustee May File Proofs of Claim.  . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .   37
         SECTION 505.  Trustee May Enforce Claims Without Possession of Debt
                        Securities. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .   37
         SECTION 506.  Application of Money Collected.  . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .   38
         SECTION 507.  Limitation on Suits. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .   39
         SECTION 508.  Unconditional Right of Holders to Receive Principal, Premium
                        and Interest. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .   39
         SECTION 509.  Restoration of Rights and Remedies.  . . . . . . . . . . . . . . . . . . . . . . . . . . . . .   40
         SECTION 510.  Rights and Remedies Cumulative.  . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .   40
         SECTION 511.  Delay or Omission Not Waiver.  . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .   40
         SECTION 512.  Control by Holders.  . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .   40
         SECTION 513.  Waiver of Past Defaults. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .   41
         SECTION 514.  Undertaking for Costs. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .   41
         SECTION 515.  Waiver of Stay or Extension Laws.  . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .   41

ARTICLE SIX

THE TRUSTEE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .   42
         SECTION 601.  Certain Duties and Responsibilities. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .   42
         SECTION 602.  Notice of Defaults . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .   43
         SECTION 603.  Certain Rights of Trustee. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .   44
         SECTION 604.  Not Responsible for Recitals or Issuance of Debt Securities. . . . . . . . . . . . . . . . . .   45
         SECTION 605.  May Hold Debt Securities.  . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .   45
         SECTION 606.  Money Held in Trust. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .   45
         SECTION 607.  Compensation, Indemnification and Reimbursement. . . . . . . . . . . . . . . . . . . . . . . .   45
         SECTION 608.  Resignation and Removal; Appointment of Successor. . . . . . . . . . . . . . . . . . . . . . .   46
         SECTION 609.  Acceptance of Appointment by Successor.  . . . . . . . . . . . . . . . . . . . . . . . . . . .   48
         SECTION 610.  Merger, Conversion, Consolidation or Succession to
                        Business. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .   49
         SECTION 611.  Appointment of Authenticating Agent. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .   50
         SECTION 612.  Preferential Collection of Claims Against Company  . . . . . . . . . . . . . . . . . . . . . .   51
</TABLE>






                                       ii

<PAGE>   4

<TABLE>
<S>                                                                                                                     <C>
ARTICLE SEVEN

CONCERNING THE HOLDERS  . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .   51
         SECTION 701.  Acts of Holders. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .   51
         SECTION 702.  Proof of Ownership; Proof of Execution of Instruments by
                        Holders.  . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .   52
         SECTION 703.  Persons Deemed Owners. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .   52
         SECTION 704.  Revocation of Consents; Future Holders Bound.  . . . . . . . . . . . . . . . . . . . . . . . .   53

ARTICLE EIGHT

HOLDERS' MEETINGS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .   53
         SECTION 801.  Purposes of Meetings.  . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .   53
         SECTION 802.  Call of Meetings by Trustee. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .   54
         SECTION 803.  Call of Meetings by Company or Holders.  . . . . . . . . . . . . . . . . . . . . . . . . . . .   54
         SECTION 804.  Qualifications for Voting. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .   54
         SECTION 805.  Regulations. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .   54
         SECTION 806.  Voting.  . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .   55
         SECTION 807.  No Delay of Rights by Meeting. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .   55
         SECTION 808.  Quorum: Action.  . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .   56

ARTICLE NINE

CONSOLIDATION, MERGER, CONVEYANCE, TRANSFER OR LEASE  . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .   56
         SECTION 901.  Company May Consolidate, etc., Only on Certain Terms.  . . . . . . . . . . . . . . . . . . . .   56
         SECTION 902.  Successor Corporation Substituted. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .   57

ARTICLE TEN

SUPPLEMENTAL INDENTURES . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .   57
         SECTION 1001.  Supplemental Indentures Without Consent of Holders. . . . . . . . . . . . . . . . . . . . . .   57
         SECTION 1002.  Supplemental Indentures With Consent of Holders.  . . . . . . . . . . . . . . . . . . . . . .   59
         SECTION 1003.  Execution of Supplemental Indentures. . . . . . . . . . . . . . . . . . . . . . . . . . . . .   60
         SECTION 1004.  Effect of Supplemental Indentures.  . . . . . . . . . . . . . . . . . . . . . . . . . . . . .   60
         SECTION 1005.  Conformity with Trust Indenture Act.  . . . . . . . . . . . . . . . . . . . . . . . . . . . .   60
         SECTION 1006.  Reference in Debt Securities to Supplemental Indentures.  . . . . . . . . . . . . . . . . . .   61
         SECTION 1007.  Notice of Supplemental Indenture. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .   61

ARTICLE ELEVEN

COVENANTS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .   61
         SECTION 1101.  Payment of Principal, Premium and Interest. . . . . . . . . . . . . . . . . . . . . . . . . .   61
         SECTION 1102.  Maintenance of Office or Agency.  . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .   61
         SECTION 1103.  Money for Debt Securities; Payments To Be Held in Trust.  . . . . . . . . . . . . . . . . . .   62
         SECTION 1104.  Corporate Existence.  . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .   63
</TABLE>






                                      iii

<PAGE>   5

<TABLE>
<S>                                                                                                                     <C>
         SECTION 1105.  Officers' Certificate as to Default.  . . . . . . . . . . . . . . . . . . . . . . . . . . . .   63

ARTICLE TWELVE

REDEMPTION OF DEBT SECURITIES . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .   64
         SECTION 1201.  Applicability of Article. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .   64
         SECTION 1202.  Election to Redeem; Notice to Trustee.  . . . . . . . . . . . . . . . . . . . . . . . . . . .   64
         SECTION 1203.  Selection by Trustee of Debt Securities to Be Redeemed. . . . . . . . . . . . . . . . . . . .   65
         SECTION 1204.  Notice of Redemption. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .   65
         SECTION 1205.  Deposit of Redemption Price.  . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .   66
         SECTION 1206.  Debt Securities Payable on Redemption Date. . . . . . . . . . . . . . . . . . . . . . . . . .   66
         SECTION 1207.  Debt Securities Redeemed in Part. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .   67

ARTICLE THIRTEEN

DEFEASANCE  . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .   67
         SECTION 1301.  Applicability of Article. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .   67
         SECTION 1302.  Defeasance Upon Deposit of Moneys or U.S. Government
                         Obligations. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .   67
         SECTION 1303.  Deposit Moneys and U.S. Government Obligations to be Held
                         in Trust.  . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .   69
         SECTION 1304.  Repayment to Company. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .   69
         SECTION 1305.  Reinstatement.  . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .   69
</TABLE>






                                       iv


<PAGE>   6
                 INDENTURE dated as of December 2, 1994, between KIRBY
CORPORATION, a Nevada corporation (hereinafter called the "Company"), having
its principal executive office at 1775 St. James Place, Suite 300, Houston,
Texas 77056 and TEXAS COMMERCE BANK NATIONAL ASSOCIATION (hereinafter called
the "Trustee"), having its Corporate Trust Office at 600 Travis Street,
8th Floor, Houston, Texas 77002.

                            RECITALS OF THE COMPANY

                 The Company has duly authorized the execution and delivery of
this Indenture to provide for the issuance from time to time of its debentures,
notes, bonds or other evidences of indebtedness (herein generally called the
"Debt Securities"), to be issued in one or more series, as provided in this
Indenture.

                 All things necessary have been done to make this Indenture a
valid agreement of the Company, in accordance with its terms.

                 NOW, THEREFORE, THIS INDENTURE WITNESSETH:

                 For and in consideration of the premises and the purchase of
Debt Securities by the Holders thereof, it is mutually covenanted and agreed,
for the equal and proportionate benefit of all Holders of Debt Securities or of
Debt Securities of any series, as follows:


                                  ARTICLE ONE

                        DEFINITIONS AND OTHER PROVISIONS
                             OF GENERAL APPLICATION

SECTION 101.  DEFINITIONS.

                 For all purposes of this Indenture, except as otherwise
expressly provided or unless the context otherwise requires:

                 (1)      the terms defined in this Article have the meanings
         assigned to them in this Article, and include the plural as well as
         the singular;

                 (2)      all other terms used herein which are defined in the
         Trust Indenture Act, either directly or by reference therein, have the
         meanings assigned to them therein;

                 (3)      all accounting terms not otherwise defined herein
         have the meanings assigned to them in accordance with generally
         accepted accounting principles, and, except as otherwise herein
         expressly provided, the term "generally accepted accounting
         principles" with respect to any computation required or permitted
         hereunder shall mean such accounting principles as are generally
         accepted in the United States of America at the date of such
         computation; and

<PAGE>   7
                 (4)      the words "herein," "hereof" and "hereunder" and
         other words of similar import refer to this Indenture as a whole and
         not to any particular Article, Section or other subdivision.

                 Certain terms, used principally in ARTICLE THREE or ARTICLE
SIX, are defined in those respective Articles.

                 "Act" when used with respect to any Holder has the meaning 
specified in SECTION 701.

                 "Affiliate" of any specified Person means any other Person
directly or indirectly controlling or controlled by or under direct or indirect
common control with such specified Person.  For the purposes of this
definition, "control" when used with respect to any specified Person means the
power to direct the management and policies of such Person, directly or
indirectly, whether through the ownership of voting securities, by contract or
otherwise; and the terms "controlling" and "controlled" have meanings
correlative to the foregoing.

                 "Authenticating Agent" has the meaning specified in SECTION
611.

                 "Board of Directors" means either the board of directors of
the Company, or the executive committee or any other committee of that board
duly authorized to act in respect hereof.

                 "Board Resolution" means a copy of a resolution certified by
the Secretary or an Assistant Secretary of the Company to have been duly
adopted by the Board of Directors and to be in full force and effect on the
date of such certification, and delivered to the Trustee.





                                       2

<PAGE>   8
                 "Business Day" when used with respect to any Place of Payment
or any other particular location referred to in this Indenture or in the Debt
Securities means any day that is not a Saturday, a Sunday or a legal holiday or
a day on which banking institutions or trust companies in that Place of Payment
or other location are authorized or obligated by law to close, except as
otherwise specified pursuant to SECTION 301.

                 "Calculation Agent" means such Person as shall be determined
by the Company from time to time.

                 "Code" means the Internal Revenue Code of 1986, as amended and
as in effect on the date hereof.

                 "Commission" means the Securities and Exchange Commission, as
from time to time constituted, created under the Securities Exchange Act of
1934, as amended, or if at any time after the execution of this instrument such
Commission is not existing and performing the duties now assigned to it under
the Trust Indenture Act, then the body performing such duties on such date.

                 "Company" means the Person named as the "Company" in the first
paragraph of this instrument until a successor Person shall have become such
pursuant to the applicable provisions of this Indenture, and thereafter
"Company" shall mean such successor Person.

                 "Company Request" and "Company Order" mean, respectively, a
written request or order signed in the name of the Company by the Chairman, a
Vice Chairman, the President, the Chief Financial Officer, a Vice President,
the Treasurer or an Assistant Treasurer, and by the Secretary or an Assistant
Secretary of the Company, and delivered to the Trustee.

                 "Component Currency" has the meaning specified in SECTION
310(H).

                 "Conversion Date" has the meaning specified in SECTION 310(D).





                                       3

<PAGE>   9
                 "Conversion Event" means the cessation of (i) a Foreign
Currency to be used both by the government of the country which issued such
Currency and for the settlement of transactions by public institutions of or
within the international banking community, (ii) the ECU to be used both within
the European Monetary System and for the settlement of transactions by public
institutions of or within the European communities, or (iii) any Currency unit
other than the ECU to be used for the purposes for which it was established.

                 "Corporate Trust Office" means the principal corporate trust
office of the Trustee at which at any particular time its corporate trust
business shall be administered, which office at the date of execution of this
instrument is located at 600 Travis Street, 8th Floor, Houston, Texas 77002.

                 "Corporation" includes corporations, associations, companies
and business trusts.

                 "Currency" means Dollars or Foreign Currency.

                 "Debt Securities" has the meaning stated in the first recital
of this Indenture and more particularly means any Debt Securities (including
any Global Notes) authenticated and delivered under this Indenture.

                 "Defaulted Interest" has the meaning specified in SECTION 307.

                 "Depositary" means a clearing agency registered under the
Securities Exchange Act of 1934, as amended, or any successor thereto, which
shall in either case be designated by the Company pursuant to SECTION 301 until
a successor Depositary shall have become such pursuant to the applicable
provisions of this Indenture, and thereafter "Depositary" shall mean or include
each Person who is then a Depositary hereunder, and if at any time there is
more than one such Person, "Depositary" as used with respect to the Debt
Securities of any series shall mean the Depositary with respect to the Debt
Securities of that series.

                 "Discharged" has the meaning specified in SECTION 1302.

                 "Discount Security" means any Debt Security that is issued
with "original issue discount" within the meaning of Section 1273(a) of the
Code and the regulations thereunder.

                 "Dollar" or "$" means a dollar or other equivalent unit in
such coin or currency of the United States of America as at the time of payment
is legal tender for the payment of public and private debts.





                                       4

<PAGE>   10
                 "Dollar Equivalent of the Currency Unit" has the meaning 
specified in SECTION 310(G).

                 "Dollar Equivalent of the Foreign Currency" has the 
meaning specified in SECTION 310(F).

                 "ECU" means the European Currency Unit as defined and revised
from time to time by the Council of the European Communities.

                 "Election Date" has the meaning specified in SECTION 310(H).

                 "Event of Default" has the meaning specified in SECTION 501.

                 "Exchange Rate Agent" means the New York Clearing
House bank, if any, from time to time selected by the Company for purposes of
SECTION 310; provided that such agent shall accept such appointment in writing
and the terms of such appointment shall be acceptable to the Company and shall,
in the opinion of the Company at the time of such appointment, require such
agent to make the determinations required by this Indenture by a method
consistent with the method provided in this Indenture for the making of such
decision or determination.

                 "Exchange Rate Officer's Certificate" means a telex or a
certificate setting forth (i) the applicable Market Exchange Rate and (ii) the
Dollar, Foreign Currency or Currency unit amounts of principal, premium, if
any, and any interest respectively (on an aggregate basis and on the basis of a
Debt Security having the lowest denomination principal amount pursuant to
SECTION 302 in the relevant Currency or Currency unit), payable on the basis of
such Market Exchange Rate sent (in the case of a telex) or signed (in the case
of a certificate) by the Chief Financial Officer, a Vice President, the
Treasurer or any Assistant Treasurer of the Company.

                 "Fixed Rate Security" means a Debt Security that provides for
the payment of interest at a fixed rate.

                 "Floating Rate Security" means a Debt Security that provides
for the payment of interest at a variable rate determined periodically by
reference to an interest rate index or any other index specified pursuant to
SECTION 301.

                 "Foreign Currency" means a currency issued by the government
of any country other than the United States or a composite currency or currency
unit the value of which is determined by reference to the values of the
currencies of any group of countries, including, but not limited to, the ECU.

                 "Global Note" means a Debt Security evidencing all or part of
a series of Debt Securities that is executed by the Company and authenticated
and delivered to the Depositary or pursuant to the Depositary's instructions,
all in accordance with this Indenture and pursuant to a Company order, which
shall be registered in the name of the Depositary or its nominee and that shall
represent the amount of uncertificated securities as specified therein.





                                       5

<PAGE>   11
                 "Holder" means a person in whose name a Debt Security of any
series is registered in the Security Register.

                 "Indenture" means this instrument as originally executed, or
as it may from time to time be supplemented or amended by one or more
indentures supplemental hereto entered into pursuant to the applicable
provisions hereof and, unless the context otherwise requires, shall include the
terms of a particular series of Debt Securities as established pursuant to
SECTION 301.

                 "Independent" when used with respect to any specified Person
means such a Person who (i) is in fact independent with respect to the Company,
(ii) does not have any direct financial interest or any material indirect
financial interest in the Company or in any other obligor upon the Debt
Securities or in any Affiliate of the Company or of such other obligor, and
(iii) is not connected with the Company or such other obligor or any Affiliate
of the Company or of such other obligor, as an officer, employee, promoter,
underwriter, trustee, partner, director or person performing similar functions.

                 The term "Interest", when used with respect to a Discount
Security which by its terms bears interest only after Maturity, means interest
payable after Maturity.

                 "Interest Payment Date" with respect to any Debt Security
means the Stated Maturity of an installment of interest on such Debt Security.

                 "Market Exchange Rate" means (i) for any conversion involving
a Currency Unit on the one hand and Dollars or any Foreign Currency on the
other, the exchange rate between the relevant Currency unit and Dollars or such
Foreign Currency calculated by the method specified pursuant to SECTION 301 for
the securities of the relevant series, (ii) for any conversion of Dollars into
any Foreign Currency, the noon (New York City time) buying rate for such
Foreign Currency for cable transfers quoted in New York City as certified for
customs purposes by the Federal Reserve Bank of New York, and (iii) for any
conversion of one Foreign currency into Dollars or another Foreign Currency,
the spot rate at noon local time in the relevant market at which, in accordance
with normal banking procedures, the Dollars or Foreign Currency into which
conversion is being made could be purchased with the Foreign Currency from
which conversion is being made from major banks located in New York City,
London or any other principal market for Dollars or such purchased Foreign
Currency.  In the event of the unavailability of any of the exchange rates
provided for in the foregoing clauses (i), (ii) and (iii) the Exchange 
Rate Agent shall use, in its sole discretion and without liability on
its part, such quotation of the Federal Reserve Bank of New York as of the most
recent available date, or quotations from one or more major banks in New York
City, London or any other principal market for such Currency or Currency unit
in question, or such other quotations as the Exchange Rate Agent shall
deem appropriate.  Unless otherwise specified by the Exchange Rate 
Agent if there is more than one market for dealing in any currency or Currency
unit by reason of foreign exchange regulations or otherwise, the market to be
used in respect of such Currency or Currency unit shall be that upon which a
nonresident issuer of securities designated in such Currency or Currency unit
would purchase such Currency or Currency unit in order to make payments in
respect of such securities.





                                       6

<PAGE>   12
                 "Maturity" when used with respect to any Debt Security means
the date on which the principal of such Debt Security or an installment of
principal becomes due and payable as therein or herein provided, whether at the
Stated Maturity or by declaration of acceleration, call for redemption,
repayment at the option of the Holder thereof or otherwise as therein or herein
provided.

                 "Mortgages" means mortgages, liens, pledges or other
encumbrances.

                 "Officers' Certificate" means a certificate signed by the
Chairman, a Vice Chairman, the President, the Chief Financial Officer, a Vice
President, the Treasurer or an Assistant Treasurer, and the Secretary or an
Assistant Secretary of the Company, and delivered to the Trustee.

                 "Opinion of Counsel" means a written opinion of counsel, who
may be counsel to the Company (including an employee of the Company) and who
shall be reasonably satisfactory to the Trustee, which is delivered to the
Trustee.

                 "Outstanding" when used with respect to Debt Securities,
means, as of the date of determination, all Debt Securities theretofore
authenticated and delivered under this Indenture, except:

                 (i)      Debt Securities theretofore canceled by the Trustee
         or delivered to the Trustee for cancellation;

                 (ii)     Debt Securities for whose payment or redemption money
         in the necessary amount has been theretofore deposited with the
         Trustee or any Paying Agent (other than the Company) in trust or set
         aside and segregated in trust by the Company (if the Company shall act
         as its own Paying Agent) for the Holders of such Debt Securities and
         any coupons thereto appertaining; provided, however, that if such Debt
         Securities are to be redeemed, notice of such redemption has been duly
         given pursuant to this Indenture or provision therefor satisfactory to
         the Trustee has been made; and

                 (iii)    Debt Securities which have been surrendered pursuant
         to SECTION 306 or in exchange for or in lieu of which other Debt
         Securities have been authenticated and delivered pursuant to this
         Indenture, other than any such Debt Securities in respect of which
         there shall have been presented to the Trustee proof satisfactory to
         it that such Debt Securities are held by a bona fide purchaser in
         whose hands such Debt Securities are valid obligations of the Company;

provided, however, that in determining whether the Holders of the requisite
principal amount of Debt Securities outstanding have performed any Act
hereunder, Debt Securities owned by the Company or any other obligor upon the
Debt Securities or any Affiliate of the Company or of such other obligor shall
be disregarded and deemed not to be Outstanding, except that, in determining
whether the Trustee shall be protected in relying upon any such Act, only Debt
Securities that the Trustee knows to be so owned shall be so disregarded.  Debt
Securities so





                                       7

<PAGE>   13
owned that have been pledged in good faith may be regarded as Outstanding if
the pledgee establishes to the satisfaction of the Trustee the pledgee's right
to act with respect to such Debt Securities and that the pledgee is not the
Company or any other obligor upon the Debt Securities or any Affiliate of the
Company or of such other obligor.  In determining whether the Holders of the
requisite principal amount of Outstanding Debt Securities have performed any
Act hereunder or whether a quorum is present at a meeting of Holders of Debt
Securities, the principal amount of a Discount Security that shall be deemed to
be Outstanding for such purpose shall be the amount of the principal thereof
that would be due and payable as of the date of such determination upon a
declaration of acceleration of the Maturity thereof pursuant to SECTION 502 and
the principal amount of a Debt Security denominated in a Foreign Currency that
shall be deemed to be Outstanding for such purpose shall be the amount
calculated pursuant to SECTION 310(J).

                 "Overdue Rate," when used with respect to any series of the
Debt Securities, means the rate designated as such in or pursuant to the Board
Resolution or the supplemental indenture, as the case may be, relating to such
series as contemplated by SECTION 301.

                 "Paying Agent" means any Person authorized by the Company to
pay the principal of (and premium, if any) or interest on any Debt Securities
on behalf of the Company.

                 "Person" means any individual, corporation, partnership, joint
venture, association, joint-stock  company, trust, estate, unincorporated
organization or government or any agency or political subdivision thereof.

                 "Place of Payment" when used with respect to the Debt
Securities of any series means the place or places where the principal of (and
premium, if any) and interest on the Debt Securities of that series are payable
as specified pursuant to SECTION 301.

                 "Predecessor Security" of any particular Debt Security means
every previous Debt Security evidencing all or a portion of the same debt as
that evidenced by such particular Debt Security; and, for the purposes of this
definition, any Debt Security authenticated and delivered under SECTION 306 in
exchange for or in lieu of a mutilated, lost, destroyed or stolen Debt Security
or a Debt Security to which a mutilated, lost, destroyed or stolen Coupon
appertains shall be deemed to evidence the same debt as the mutilated, lost,
destroyed or stolen Debt Security or the Debt Security to which the mutilated,
lost, destroyed or stolen Coupon appertains, as the case may be.

                 "Redemption Date" means the date fixed for redemption of any
Debt Security pursuant to this Indenture which, in the case of a Floating Rate
Security, unless otherwise specified pursuant to SECTION 301, shall be an
Interest Payment Date only.





                                       8

<PAGE>   14
                 "Redemption Price" means, in the case of a Discount Security,
the amount of the principal thereof that would be due and payable as of the
Redemption Date upon a declaration of acceleration of the maturity thereof
pursuant to SECTION 502, and in the case of any other Debt Security, the
principal amount thereof, plus, in each case, premium, if any, and accrued and
unpaid interest, if any, to the Redemption Date.

                 "Regular Record Date" for the interest payable on the Debt
Securities of any series on any Interest Payment Date means the date specified
for the purpose pursuant to SECTION 301 for such Interest Payment Date.

                 "Responsible Officer" when used with respect to the Trustee
means any Vice President, the Secretary, any Assistant Secretary, any Trust
Officer or Assistant Trust Officer, or any other officer of the Trustee
customarily performing functions similar to those performed by any of the above
designated officers and also means, with respect to a particular corporate
trust matter, any other officer to whom such matter is referred because of his
knowledge of and familiarity with the particular subject.

                 "Security Register" and "Security Registrar" have the
respective meanings specified in SECTION 305(A).

                 "Significant Subsidiary" means any Subsidiary that would be 
a "significant subsidiary" under the definition therefor in Regulation Section 
210.1-02 of Regulation S-X of the Rules and Regulations adopted pursuant to 
the Securities Act of 1933 and the Securities Exchange Act of 1934, as in 
effect from time to time, or any successor statutes or regulations.

                 "Special Record Date" for the payment of any Defaulted
Interest means a date fixed by the Paying Agent pursuant to SECTION 307.

                 "Specified Amount" has the meaning specified 
in SECTION 310(H).                  

                 "Stated Maturity" when used with respect to any Debt Security
or any installment of principal thereof or premium thereon or interest thereon
means the date specified in such Debt Security as the date on which the
principal of such Debt Security or such installment of principal, premium or
interest is due and payable.

                 "Subsidiary" means (i) any corporation of which at least a
majority of the outstanding stock having by the terms thereof ordinary voting
power to elect a majority of the directors of such corporation, irrespective of
whether or not at the time stock of any other class or classes of such
corporation shall have or might have voting power by reason of the happening of
any contingency, is at the time, directly or indirectly, owned or controlled by
the Company or by one or more Subsidiaries thereof, or by the Company and one
or more Subsidiaries or (ii) any partnership or joint venture of which at least
a majority of the equity ownership, whether in the form of membership, general,
special or limited partnership interests or otherwise, is directly or
indirectly owned or controlled by the Company or by one or more Subsidiaries
thereof, or by the Company and one or more Subsidiaries.





                                       9

<PAGE>   15
                 "Trust Indenture Act" means the Trust Indenture Act of 1939,
as amended and in force at the date as of which this instrument was executed,
except as provided in SECTION 1005.

                 "Trustee" means the Person named as the "Trustee" in the first
paragraph of this instrument until a successor Trustee shall have become such
pursuant to the applicable provisions of this Indenture, and thereafter
"Trustee" shall mean or include each Person who is then a Trustee hereunder,
and if at any time there is more than one such Person, "Trustee," as used with
respect to the Debt Securities of any series, shall mean the Trustee with
respect to Debt Securities of such series.

                 "U.S. Government Obligations" has the meaning specified in 
SECTION 1302.

                 "Valuation Date" has the meaning specified in SECTION 310(C).

                 "Vice President" includes with respect to the Company and the
Trustee, any Vice President of the Company or the Trustee, as the case may be,
whether or not designated by a number or word or words added before or after
the title "Vice President."

SECTION 102.  COMPLIANCE CERTIFICATES AND OPINIONS.

                 Upon any application or request by the Company to the Trustee
to take any action or refrain from taking any action under any provision of
this Indenture, the Company shall furnish to the Trustee an Officers'
Certificate stating that all conditions precedent, if any, provided for in this
Indenture relating to the proposed action have been complied with and an
Opinion of Counsel stating that in the opinion of such counsel all such
conditions precedent, if any, have been complied with, except that in the case
of any such application or request as to which the furnishing of such documents
is specifically required by any provision of this Indenture relating to such
particular application or request, no additional certificate or opinion need be
furnished.

                 Every certificate or opinion with respect to compliance with a
condition or covenant provided for in this Indenture shall include:

                 (1)      a statement that each individual signing such
         certificate or opinion has read such covenant or condition and the
         definitions herein relating thereto;





                                       10

<PAGE>   16
                 (2)      a brief statement as to the nature and scope of the
         examination or investigation upon which the statements or opinions
         contained in such certificate or opinion are based;

                 (3)      a statement that, in the opinion of each such
         individual, he has made such examination or investigation as is
         necessary to enable him to express an informed opinion as to whether
         or not such covenant or condition has been complied with; and

                 (4)      a statement as to whether, in the opinion of each
         such individual, such condition or covenant has been complied with.

SECTION 103.  FORM OF DOCUMENTS DELIVERED TO TRUSTEE.

                 In any case where several matters are required to be certified
by, or covered by an opinion of, any specified Person, it is not necessary that
all such matters be certified by, or covered by the opinion of, only one such
Person, or that they be so certified or covered by only one document, but one
such Person may certify or give an opinion with respect to some matters and one
or more other such Persons as to other matters, and any such Person may certify
or give an opinion as to such matters in one or several documents.

                 Any certificate or opinion of an officer of the Company may be
based, insofar as it relates to legal matters, upon a certificate or opinion
of, or representations by, counsel, unless such officer knows, or in the
exercise of reasonable care should know, that the certificate or opinion or
representations with respect to the matters upon which his certificate or
opinion is based are erroneous.  Any such certificate or Opinion of Counsel may
be based, insofar as it relates to factual matters, upon a certificate or
opinion of, or representations by, an officer or officers of the Company
stating that the information with respect to such factual matters is in the
possession of the Company, unless such counsel knows, or in the exercise of
reasonable care should know, that the certificate or opinion or representations
with respect to such matters are erroneous.

                 Where any Person is required to make, give or execute two or
more applications, requests, consents, certificates, statements, opinions or
other instruments under this Indenture, they may, but need not, be consolidated
and form one instrument.

SECTION 104.  NOTICES, ETC., TO TRUSTEE, PAYING AGENT AND COMPANY.

                 Any Act of Holders or other document provided or permitted by
this Indenture to be made upon, given or furnished to, or filed with:

                 (1)      the Trustee by any Holder or by the Company shall be
         sufficient for every purpose hereunder (unless otherwise herein
         expressly provided) if made, given, furnished or filed in writing to
         or with the Trustee at its Corporate Trust Office, Attention:
         Vice President, Corporate Trust Department;





                                       11

<PAGE>   17
                 (2)      the Company by the Trustee or by any Holder shall be
         sufficient for every purpose hereunder (unless otherwise herein
         expressly provided) if in writing and mailed, first-class postage
         prepaid or airmail postage prepaid if sent from outside the United
         States, to the Company addressed to it at the address of its principal
         office specified in the first paragraph of this instrument, to the
         attention of its Treasurer, or at any other address previously
         furnished in writing to the Trustee by the Company, or
                 
                 (3)      the Paying Agent by any Holder or by the Company
         shall be sufficient for every purpose hereunder (unless otherwise 
         herein expressly provided) if made, given, furnished or filed in 
         writing to or with the Paying Agent at the address for the Paying 
         Agent provided pursuant to Section 301 or Section 305(c) or any
         supplemental Indenture.
                 
                 Any such Act or other document shall be in the English
language, except that any published notice may be in an official language of
the country of publication.

SECTION 105.  NOTICE TO HOLDERS; WAIVER.

                 Where this Indenture provides for notice to Holders of any
event, such notice shall be sufficiently given to Holders (unless otherwise
herein expressly provided) if in writing and mailed, first-class postage
prepaid, to such Holders as their names and addresses appear in the Security
Register, within the time prescribed; provided, however, that any notice to
Holders of Floating Rate Securities regarding the determination of a periodic
rate of interest, if such notice is required pursuant to SECTION 301, shall be
sufficiently given if given in the manner specified pursuant to SECTION 301.

                 In the event of suspension of regular mail service or by
reason of any other cause it shall be impracticable to give notice by mail,
such notification shall be given by telex, telecopy or other facsimile
transmission.

                 Where this Indenture provides for notice in any manner, such
notice may be waived in writing by the Person entitled to receive such notice,
either before or after the event, and such waiver shall be the equivalent of
such notice.  Waivers of notice by Holders shall be filed with the Trustee, but
such filing shall not be a condition precedent to the validity of any action
taken in reliance on such waiver.  In any case where notice to Holders is given
by mail, neither the failure to mail such notice nor any defect in any notice
so mailed to any particular Holder, shall affect the sufficiency of such notice
with respect to other Holders, and any notice which is mailed in the manner
herein provided shall be conclusively presumed to have been duly given.

SECTION 106.  CONFLICT WITH TRUST INDENTURE ACT.

                 If and to the extent that any provision of this Indenture
limits, qualifies or conflicts with another provision included in this
Indenture by operation of Sections 310 to 317, inclusive, of the Trust
Indenture Act (an "incorporated provision"), such incorporated provision shall
control.

SECTION 107.  EFFECT OF HEADINGS AND TABLE OF CONTENTS.

                 The Article and Section headings herein and the Table of
Contents are for convenience only and shall not affect the construction hereof.





                                       12

<PAGE>   18
SECTION 108.  SUCCESSORS AND ASSIGNS.

                 All covenants and agreements in this Indenture by the parties
hereto shall bind their respective successors and assigns and inure to the
benefit of their permitted successors and assigns, whether so expressed or not.

SECTION 109.  SEPARABILITY CLAUSE.

                 In case any provision in this Indenture or in the Debt
Securities shall be invalid, illegal or unenforceable, the validity, legality
and enforceability of the remaining provisions shall not in any way be affected
or impaired thereby.

SECTION 110.  BENEFITS OF INDENTURE.

                 Nothing in this Indenture or in the Debt Securities, express
or implied, shall give to any Person, other than the parties hereto, any
Security Registrar, any Paying Agent and their successors hereunder, and the
Holders, any benefit or any legal or equitable right, remedy or claim under
this Indenture.

SECTION 111.  GOVERNING LAW.

                 This Indenture and the Debt Securities shall be deemed to be
contracts made and to be performed entirely in the State of New York, and for
all purposes shall be governed by and construed in accordance with the laws of
said State without regard to the conflicts of law rules of said State.

SECTION 112.  LEGAL HOLIDAYS.

                 Unless otherwise specified pursuant to SECTION 301 or in any
Debt Security, in any case where any Interest Payment Date, Redemption Date or
Stated Maturity of any Debt Security of any series shall not be a Business Day
at any Place of Payment for the Debt Securities of that series, then
(notwithstanding any other provision of this Indenture or of the Debt
Securities) payment of principal (and premium, if any) or interest need not be
made at such Place of Payment on such date, but may be made on the next
succeeding Business Day at such Place of Payment with the same force and effect
as if made on the Interest Payment Date, Redemption Date or at the Stated
Maturity, and no interest shall accrue on the amount so payable for the period
from and after such Interest Payment Date, Redemption Date or Stated Maturity,
as the case may be, to such Business Day if such payment is made or duly
provided for on such Business Day.

SECTION 113.  NO SECURITY INTEREST CREATED.

                 Nothing in this Indenture or in the Debt Securities, express
or implied, shall be construed to constitute a security interest under the
Uniform Commercial Code or similar





                                       13

<PAGE>   19
legislation, as now or hereafter enacted and in effect in any jurisdiction
where property of the Company or its Subsidiaries is or may be located.

SECTION 114.  LIABILITY SOLELY CORPORATE.

                 No recourse shall be had for the payment of the principal of
(or premium, if any) or the interest on any Debt Securities, or any part
thereof, or of the indebtedness represented thereby, or upon any obligation,
covenant or agreement of this Indenture, against any incorporator, or against
any stockholder, officer or director, as such, past, present or future, of the
Company (or any incorporator, stockholder, officer or director of any
predecessor or successor corporation), either directly or through the Company
(or any such predecessor or successor corporation), whether by virtue of any
constitution, statute or rule of law, or by the enforcement of any assessment
or penalty or otherwise; it being expressly agreed and understood that this
Indenture and all the Debt Securities are solely corporate obligations, and
that no personal liability whatsoever shall attach to, or be incurred by, any
such incorporator, stockholder, officer or director, past, present or future,
of the Company (or any incorporator, stockholder, officer or director of any
such predecessor or successor corporation), either directly or indirectly
through the Company or any such predecessor or successor corporation, because
of the indebtedness hereby authorized or under or by reason of any of the
obligations, covenants, promises or agreements contained in this Indenture or
in any of the Debt Securities or to be implied herefrom or therefrom; and that
any such personal liability is hereby expressly waived and released as a
condition of, and as part of the consideration for, the execution of this
Indenture and the issue of securities; provided, however, that nothing herein
or in the Debt Securities contained shall be taken to prevent recourse to and
the enforcement of the liability, if any, of any stockholder or subscriber to
capital stock upon or in respect of the shares of capital stock not fully paid.

SECTION 115.  INTEREST LIMITATION.

                 It is the intention of the Company to conform strictly to all
applicable usury laws and any subsequent revisions, repeals or judicial
interpretations thereof.  Accordingly, if the transactions contemplated hereby
would be usurious under any applicable law then, in that event, notwithstanding
anything to the contrary in the Debt Securities or this Indenture, it is agreed
as follows: (a) the aggregate of all consideration which constitutes interest
under applicable law that is contracted for, taken, reserved, charged,
collected or received under a Debt Security or this Indenture or otherwise in
connection with such Debt Security shall under no circumstances exceed the
maximum amount allowed by applicable law, and any excess shall be credited to
the principal amount of such Debt Security (or, if the principal amount of such
Debt Security shall have been paid in full, refunded to the Company); and (b)
in the event that the Maturity of any Debt Security is accelerated or in the
event of any redemption or defeasance of such Debt Security, then such
consideration that constitutes interest under applicable law may never include
more than the maximum amount allowed by applicable law, and excess interest, if
any, provided for in this Indenture or such Debt Security or otherwise shall be
cancelled automatically as of the date of such acceleration, redemption or
defeasance and, if theretofore paid, shall be credited to the principal amount
of such Debt Security (or, if the principal amount of such Debt Security





                                       14

<PAGE>   20
shall have been paid in full, refunded by such Holder to the Company), to the
extent permitted by applicable law.  All calculations made to compute the rate
of interest that is contracted for, taken, reserved, charged, collected or
received under any Debt Security or under this Indenture or otherwise in
connection with such Debt Security for the purpose of determining whether such
rate exceeds the maximum amount allowed by applicable law shall be made, to the
extent permitted by such applicable law, by amortizing, prorating, allocating
and spreading during the period of the full stated term of such Debt Security
all interest any time contracted for, taken, reserved, charged or received by   
such Holder or by the Trustee or the Paying Agent on behalf of any such Holder
in connection therewith so that the amount or rate of interest charged for any
and all periods of time during the term of the Debt Security is to the greatest
extent possible less than the maximum amount or rate of interest allowed to be
charged by law during the relevant period of time.  Notwithstanding any of the
foregoing, if at any time applicable laws shall be changed so as to permit a
higher rate or amount of interest to be charged than that permitted prior to
such change, then unless prohibited by law, references in this Indenture or any
Debt Security to "applicable law" when used in the context of determining the
maximum interest or rate of interest that can be charged shall be deemed to
refer to such applicable law as so amended to allow the greater amount or rate
of interest.

                 Neither the Trustee nor the Paying Agent shall have any 
responsibility to determine whether any payments with respect to the Debt 
Securities are in compliance with any applicable usury laws and subsequent 
revisions, repeals or judicial interpretations thereof.  Notwithstanding any 
provision of this Indenture or the Debt Securities, the Trustee and any Paying 
Agent (other than the Company) may continue to make payments on the Debt 
Securities without regard to the application of this Section unless and until 
it shall have received from the Company, in conformity with Sections 102 and 
103 of this Indenture, (i) an Opinion of Counsel to the effect that, as the 
result of a final judicial interpretation by a court of competent jurisdiction, 
any payments with respect to the Debt Securities will exceed the maximum amount
allowed by applicable law and that any direction to the Trustee or the Paying   
Agent by the Company for action under this Section is in compliance with all
applicable laws and the provisions of this Indenture and the Debt Securities
and (ii) an Officers' Certificate setting forth the action required to be taken
with respect to the Debt Securities pursuant to this Section, together with any
computations or calculations with respect thereof, and stating that such action
is in compliance with the provisions of this Indenture and the Debt Securities.

SECTION 116.  COUNTERPARTS.

                This Indenture may be executed in any number of counterparts,
each of which shall be an original; but such counterparts shall together
constitute but one and the same instrument.





                                       15

<PAGE>   21
                                  ARTICLE TWO

                              DEBT SECURITY FORMS

SECTION 201.  FORMS GENERALLY.

                 The Debt Securities of each series shall be substantially in
one of the forms (including global form) established in or pursuant to a Board
Resolution or one or more indentures supplemental hereto, and shall have such
appropriate insertions, omissions, substitutions and other variations as are
required or permitted by this Indenture, and may have such letters, numbers or
other marks of identification or designation and such legends or endorsements
placed thereon as the Company may deem appropriate and as are not inconsistent
with the provisions of this Indenture, or as may be required to comply with any
law or with any rule or regulation made pursuant thereto or with any rule or
regulation of any securities exchange on which any series of the Debt
Securities may be listed, or to conform to usage, all as determined by the
officers executing such Debt Securities as conclusively evidenced by their
execution of such Debt Securities.  If the form of a series of Debt Securities
(or any Global Note) is established in or pursuant to a Board Resolution, a
copy of such Board Resolution shall be delivered to the Trustee, together with
an Officers' Certificate setting forth the form of such series, at or prior to
the delivery of the Company Order contemplated by SECTION 303 for the
authentication and delivery of such Debt Securities (or any such Global Note).

                  The definitive Debt Securities of each series shall be
printed, lithographed or engraved or produced by any combination of these
methods on steel engraved borders or may be produced in any other manner, all
as determined by the officers executing such Debt Securities, as conclusively
evidenced by their execution of such Debt Securities.

SECTION 202.  FORM OF TRUSTEE'S CERTIFICATE OF AUTHENTICATION.

                 The form of the Trustee's certificate of authentication to be
borne by the Debt Securities shall be substantially as follows:


                    TRUSTEE'S CERTIFICATE OF AUTHENTICATION

                 This is one of the series of Debt Securities issued under the
within mentioned Indenture.

                                                   TEXAS COMMERCE BANK NATIONAL
                                                   ASSOCIATION, as Trustee



                                                   By __________________________
                                                         Authorized Signatory





                                       16

<PAGE>   22
                                 ARTICLE THREE

                              THE DEBT SECURITIES

SECTION 301.  AMOUNT UNLIMITED; ISSUABLE IN SERIES.

                 The aggregate principal amount of Debt Securities that may be
authenticated and delivered under this Indenture is limited to $250,000,000
(or, with respect to any series of Debt Securities issued in a Foreign
Currency, its equivalent based upon the applicable Market Exchange Rate at the
time of issuance).

                 The Debt Securities may be issued in one or more series.
There shall be established in one or more indentures supplemental hereto or in
or pursuant to a Board Resolution accompanied by an Officers' Certificate prior
to the issuance of Debt Securities of any series:

                 (1)      the title of the Debt Securities of the series (which
         shall distinguish the Debt Securities of such series from all other
         series of Debt Securities);

                 (2)      the limit, if any, upon the aggregate principal
         amount of the Debt Securities of the series that may be authenticated
         and delivered under this Indenture (except for Debt Securities
         authenticated and delivered upon transfer of, or in exchange for, or
         in lieu of, other Debt Securities of such series pursuant to SECTIONS
         304, 305, 306, 1006 or 1207 and except for any Debt Securities that,
         pursuant to SECTION 303, are deemed never to have been authenticated
         and delivered hereunder);

                 (3)      the date or dates on which or periods during which
         the Debt Securities of the series may be issued, and the date or dates
         (or the method of determination thereof) on which the principal of
         (and premium, if any, on) the Debt Securities of such series are or
         may be payable (which, if so provided in such Board Resolution or
         supplemental indenture may be determined by the Company from time to
         time and set forth in the Debt Securities of the series issued from
         time to time);

                 (4)      the rate or rates (or the method of determination
         thereof) at which the Debt Securities of the series shall bear
         interest, if any, and the dates from which such interest shall accrue
         (which, in either case or both, if so provided in such Board
         Resolution or supplemental indenture may be determined by the Company
         from time to time and set forth in the Debt Securities of the series
         issued from time to time), the Interest Payment Dates on which such
         interest shall be payable (or the method of determination thereof),
         and the Regular Record Dates for the interest payable on such Interest
         Payment Dates and, in the case of Floating Rate Securities, the
         notice, if any, to Holders regarding the determination of interest and
         the manner of giving such notice, and the extent to which, or the
         manner in which, any interest payable on any Global Note on an
         Interest Payment Date will be paid if other than in the manner
         provided in SECTION 307;





                                       17

<PAGE>   23
                 (5)      the place or places where the principal of (and 
         premium, if any) an interest on Debt Securities of the series shall 
         be payable by the Company;

                 (6)      the obligation, if any, of the Company to redeem or
         purchase Debt Securities of the series at the option of the Holder and
         the period or periods within which or the dates on which, the prices
         at which and the terms and conditions upon which Debt Securities of
         the series shall be redeemed, repaid or purchased, in whole or in
         part, pursuant to such obligation;

                 (7)      the period or periods within which or the date or
         dates on which, the price or prices at which and the terms and
         conditions upon which Debt Securities of the series may be redeemed,
         if any, in whole or in part, at the option of the Company or
         otherwise;

                 (8)      if the coin or Currency in which the Debt Securities
         shall be issuable is in Dollars, the denominations of such Debt
         Securities if other than denominations of $1,000 and any integral
         multiple thereof (except as provided in SECTION 304);

                 (9)      whether the Debt Securities of the series are to be
         issued as Discount Securities and the amount of discount with which
         such Debt Securities may be issued and, if other than the principal
         amount thereof, the portion of the principal amount of Debt Securities
         of the series which shall be payable upon declaration of acceleration
         of the Maturity thereof pursuant to SECTION 502;

                 (10)     provisions, if any, for the defeasance of Debt
         Securities of the series;

                 (11)     if other than Dollars, the Foreign Currency or
         Currencies in which Debt Securities of the series shall be
         denominated, or in which payment of the principal of (and/or premium,
         if any) and/or interest on the Debt Securities of the series may be
         made, and the particular provisions applicable thereto and, if
         applicable, the amount of Debt Securities of the series which entitles
         the Holder of a Debt Security of the series or proxy to one vote for
         purposes of SECTION 805;

                 (12)     if the principal of (and premium, if any) or interest
         on Debt Securities of the series are to be payable, at the election of
         the Company or a Holder thereof, in a Currency other than that in
         which the Debt Securities are denominated or payable without such
         election, in addition or in lieu of the provisions of SECTION 310, the
         period or periods within which and the terms and conditions upon which
         such election may be made and the time and the manner of determining
         the exchange rate or rates between the Currency or Currencies in which
         the Debt Securities are denominated or payable without such election
         and the Currency or Currencies in which the Debt Securities are to be
         paid if such election is made;





                                       18

<PAGE>   24
                 (13)     the date as of which any Global Note representing any
         Outstanding Debt Securities of the series shall be dated if other than
         the date of original issuance of the first Debt Security of the series
         to be issued;

                 (14)     if the amount of payments of principal of (and
         premium, if any) or interest on the Debt Securities of the series may
         be determined with reference to an index including, but not limited
         to, an index based on a Currency or Currencies other than that in
         which the Debt Securities are denominated or payable, or any other
         type of index, the manner in which such amounts shall be determined;

                 (15)     if the Debt Securities of the series are denominated
         or payable in a Foreign Currency, any other terms concerning the
         payment of principal of (and premium, if any) or any interest on such
         Debt Securities (including the Currency or Currencies of payment
         thereof);

                 (16)     the designation of the Exchange Rate Agent with
         respect to the series;

                 (17)     the applicable Overdue Rate, if any;

                 (18)     the applicable dates for purposes of Section 312(a) 
         of the Trust Indenture Act;

                 (19)     any addition to, or modification or deletion of, any
         Events of Default or covenants provided for with respect to Debt
         Securities of the series;

                 (20)     whether the Debt Securities of the series shall be
         issued in whole or in part in the form of one or more Global Notes
         and, in such case, the Depositary for such Global Note or Notes;

                 (21)     the Person who shall be the Security Registrar
         or Paying Agent with respect to the Debt Securities of the series, and

                 (22)     the designation of the Calculation Agent, if any, and
         the duties and responsibilities thereof; and

                 (23)     any other terms of the series (which terms shall not
         be inconsistent with the provisions of this Indenture).

                 All Debt Securities of any one series shall be substantially
identical except as to denomination, rate of interest, Stated Maturity and the
date from which interest, if any, shall accrue, which, as set forth above, may
be determined by the Company from time to time as to Debt Securities of a
series.  All Debt Securities of any one series need not
be issued at the same time, and unless otherwise provided, a series may be
reopened for issuance of additional Debt Securities of such series.





                                       19

<PAGE>   25
                 If any of the terms of a series of Debt Securities is
established in or pursuant to a Board Resolution, a copy of such Board
Resolution shall be certified by the Secretary or an Assistant Secretary of the
Company and delivered to the Trustee at or prior to the delivery of the
Officers' Certificate setting forth the terms of the series.

SECTION 302.  DENOMINATIONS.

                 In the absence of any specification pursuant to SECTION 301
with respect to Debt Securities of any series, the Debt Securities of such
series shall be issuable only in registered form and in denominations of $1,000
and any integral multiple thereof and shall be payable only in Dollars.

SECTION 303.  EXECUTION, AUTHENTICATION, DELIVERY AND DATING.

                 The Debt Securities of any series shall be executed on behalf
of the Company by its Chairman, a Vice Chairman, its President, its Chief
Financial Officer, one of its Vice Presidents or its Treasurer, under its
corporate seal reproduced thereon or affixed thereto and attested by its
Secretary or one of its Assistant Secretaries.  The signature of any of these
officers on the Debt Securities may be manual or facsimile.

                 Debt Securities bearing the manual or facsimile signatures of
individuals who were at any time the proper officers of the Company shall bind
the Company, notwithstanding that such individuals or any of them have ceased
to hold such offices prior to the authentication and delivery of such Debt
Securities or did not hold such offices at the date of such Debt Securities.

                 At any time and from time to time after the execution and
delivery of this Indenture, the Company may deliver Debt Securities of any
series, executed by the Company, to the Trustee for authentication, together
with a Company Order for the authentication and delivery of such Debt
Securities, and the Trustee in accordance with the Company Order shall
authenticate and deliver such Debt Securities.  If all the Debt Securities of
any one series are not to be issued at one time and if a Board Resolution or
supplemental indenture relating to such series shall so permit, such Company
Order may set forth procedures acceptable to the Trustee and the Paying Agent
for the issuance of such Debt Securities such as interest rate, Stated 
Maturity, date of issuance and date from which interest, if any, shall accrue.

                 In authenticating Debt Securities hereunder, the Trustee shall
be entitled to receive, and (subject to any incorporated provisions) shall be
fully protected in relying upon, prior to the authentication and delivery of
the Debt Securities of a particular series, (i) the supplemental indenture or
the Board Resolution by or pursuant to which the form and terms of such Debt
Securities have been approved, (ii) an Officer's Certificate stating that no
Event of Default shall have occurred and be continuing, and (iii) an Opinion of
Counsel stating that:

                 (1)      all instruments furnished by the Company to the
         Trustee in connection with the authentication and delivery of such
         Debt Securities conform to the requirements of





                                       20

<PAGE>   26
         this Indenture and constitute sufficient authority hereunder for the
         Trustee to authenticate and deliver such Debt Securities;

                 (2)      the forms and terms of such Debt Securities have been
         established in conformity with the provisions of this Indenture;

                 (3)      in the event that the forms or terms of such Debt
         Securities have been established in a supplemental indenture, the
         execution and delivery of such supplemental indenture has been duly
         authorized by all necessary corporate action of the Company, such
         supplemental indenture has been duly executed and delivered by the
         Company and, assuming due authorization, execution and delivery by the
         Trustee, is a valid and binding obligation enforceable against the
         Company in accordance with its terms, subject to applicable
         bankruptcy, insolvency and similar laws affecting creditors' rights
         generally and subject, as to enforceability, to general principles of
         equity (regardless of whether enforcement is sought in a proceeding in
         equity or at law);

                 (4)      the execution and delivery of such Debt Securities
         have been duly authorized by all necessary corporate action of the
         Company and such Debt Securities have been duly executed by the
         Company, and, assuming due authentication by the Trustee and delivery
         by the Company, are valid and binding obligations enforceable against
         the Company in accordance with their terms, entitled to the benefit of
         the Indenture, subject to applicable bankruptcy, insolvency and
         similar laws affecting creditors' rights generally and subject, as to
         enforceability, to general principles of equity (regardless of whether
         enforcement is sought in a proceeding in equity or at law) and subject
         to such other exceptions as counsel shall request and as to which the
         Trustee shall not reasonably object; and

                 (5)      the amount of Debt Securities Outstanding of such
         series, together with the amount of such Debt Securities, does not
         exceed any limit established under the terms of this Indenture on the
         amount of Debt Securities of such series that may be authenticated and
         delivered.

                 The Trustee shall not be required to authenticate such Debt
Securities if the issuance of such Debt Securities pursuant to this Indenture
will affect the Trustee's own rights, duties or immunities under the Debt
Securities and this Indenture in a manner which is not reasonably acceptable to
the Trustee.

                 Each Debt Security shall be dated the date of its
authentication.

                 No Debt Security shall be entitled to any benefit under this
Indenture or be valid or obligatory for any purpose unless there appears on
such Debt Security a certificate of authentication substantially in one of the
forms provided for herein duly executed by the Trustee or by an Authenticating
Agent, and such certificate upon any Debt Security shall be conclusive
evidence, and the only evidence, that such Debt Security has been duly
authenticated and delivered hereunder and is entitled to the benefits of this
Indenture. 





                                       21

<PAGE>   27
SECTION 304.  TEMPORARY DEBT SECURITIES; GLOBAL NOTES.

                 (a)       Pending the preparation of definitive Debt
Securities of any series, the Company may execute, and upon Company Order the
Trustee shall authenticate and deliver, temporary Debt Securities which are
printed, lithographed, typewritten, mimeographed or otherwise produced, in any
authorized denomination for Debt Securities of such series, substantially of
the tenor of the definitive Debt Securities in lieu of which they are issued
and with such appropriate insertions, omissions, substitutions and other
variations as the officers executing such Debt Securities may determine, as
conclusively evidenced by their execution of such Debt Securities.  Every such
temporary Debt Security shall be executed by the Company and shall be
authenticated and delivered by the Trustee upon the same conditions and in
substantially the same manner, and with the same effect, as the definitive Debt
Securities in lieu of which they are issued.

                 If temporary Debt Securities of any series are issued, the
Company will cause definitive Debt Securities of such series to be prepared
without unreasonable delay.  After the preparation of definitive Debt
Securities of such series, the temporary Debt Securities of such series shall
be exchangeable for definitive Debt Securities of such series, of a like Stated
Maturity and with like terms and provisions, upon surrender of the temporary
Debt Securities of such series at the office or agency of the Security
Registrar without charge to the Holder, except as provided in SECTION 305 in
connection with a transfer.  Upon surrender for cancellation of any one or more
temporary Debt Securities of any series, the Company shall execute and the
Trustee shall authenticate and deliver in exchange therefor a like principal
amount of definitive Debt Securities of the same series of authorized
denominations and of a like Stated Maturity and like terms and provisions. 
Until so exchanged, the temporary Debt Securities of any series shall in all
respects be entitled to the same benefits under this Indenture as definitive
Debt Securities of such series.

                 (b)      If the Company shall establish pursuant to SECTION
301 that the Debt Securities of a series are to be issued in whole or in part
in the form of one or more Global Notes, then the Company shall execute and the
Trustee shall, in accordance with SECTION 303 and the Company Order with
respect to such series, authenticate and deliver one or more Global Notes in
temporary or permanent form that (i) shall represent and shall be denominated
in an amount equal to the aggregate principal amount of the outstanding Debt
Securities of such series to be represented by one or more Global Notes, (ii)
shall be registered by the Security Registrar in the name of the Depositary 
for such Global Note or Notes or the nominee of such Depositary, (iii) shall be
delivered by the Trustee to such Depositary or pursuant to such Depositary's
instruction, and





                                       22

<PAGE>   28
(iv) shall bear a legend substantially to the following effect: "Unless and
until it is exchanged in whole or in part for Debt Securities in definitive
form, this Debt Security may not be transferred except as a whole by the
Depositary to a nominee of the Depositary or by a nominee of the Depositary to
the Depositary or another nominee of the Depositary or by the Depositary or any
such nominee to a successor Depositary or a nominee of such successor
Depositary."

                 Notwithstanding any other provision of this Section or SECTION
305, unless and until it is exchanged in whole or in part for Debt Securities
in definitive form, a Global Note representing all or a portion of the Debt
Securities of a series may not be transferred except as a whole by the
Depositary for such series to a nominee of such Depositary or by a nominee of
such Depositary to such Depositary or another nominee of such Depositary or by
such Depositary or any such nominee to a successor Depositary for such series
or a nominee of such successor Depositary.

                 If at any time the Depositary for the Debt Securities of a
series notifies the Company that it is unwilling or unable to continue as
Depositary for the Debt Securities of such series or if at any time the
Depositary for Debt Securities of a series ceases to be a clearing agency
registered under the Securities Exchange Act of 1934, as amended, or other
applicable statute or regulation, the Company shall appoint a successor
Depositary with respect to the Debt Securities of such series.  If a successor
Depositary for the Debt Securities of such series is not appointed by the
Company within 90 days after the Company receives such notice or becomes aware
of such condition, the Company will execute, and the Trustee, upon receipt of a
Company Order for the authentication and delivery of definitive Debt Securities
of such series, will authenticate and deliver, Debt Securities of such series
in definitive form in an aggregate principal amount equal to the principal
amount of the Global Note or Notes representing such series in exchange for
such Global Note or Notes.

                 The Company may at any time and in its sole discretion
determine that the Debt Securities of any series issued in the form of one or
more Global Notes shall no longer be represented by such Global Note or Notes.
In such event, or in the event of the occurrence and continuation of an Event
of Default with respect to Debt Securities of a series, the Company will
execute, and the Trustee, upon receipt of a Company Order for the
authentication and delivery of definitive Debt Securities of such series, will
authenticate and deliver, Debt Securities of such series in definitive form and
in an aggregate principal amount equal to the principal amount of the Global
Note or Notes representing such series in exchange for such Global Note or
Notes.

                 If specified by the Company pursuant to SECTION 301 with
respect to Debt Securities of a series, the Depositary for such series of Debt
Securities may surrender a Global Note for such series of Debt Securities in
exchange in whole or in part for Debt Securities of such series in definitive
form on such terms as are acceptable to the Company and such Depositary.
Thereupon, the Company shall execute and the Trustee shall authenticate and
deliver, without charge:

                 (i)      to each Person specified by the Depositary a new Debt
         Security or Securities of the same series of any authorized
         denomination as requested by such Person





                                       23

<PAGE>   29
         in aggregate principal amount equal to and in exchange for such
         Person's beneficial interest in the Global Note; and

                 (ii)     to the Depositary a new Global Note in a denomination
         equal to the difference, if any, between the principal amount of the
         surrendered Global Note and the aggregate principal amount of Debt
         Securities delivered to Holders thereof.

                 Upon the exchange of a Global Note for Debt Securities in
definitive form, such Global Note shall be canceled by the Security Registrar. 
Debt Securities issued in exchange for a Global Note pursuant to this SECTION
304 shall be registered in such names and in such authorized denominations as
the Depositary for such Global Note, pursuant to instructions from its direct
or indirect participants or otherwise, shall instruct the Trustee.  The Trustee
shall deliver such Debt Securities to the persons in whose names such Debt
Securities are so registered.

SECTION 305.  REGISTRATION, TRANSFER AND EXCHANGE.

                 (a)      The Company shall cause to be kept at the principal
office of the Security Registrar a register (the registers maintained in such
office and in any other office or agency of the Company, the Security Registrar
or the Paying Agent being herein sometimes collectively referred to as the
"Security Register") in which, subject to such reasonable regulations as it
may prescribe, the Company shall provide for the registration of the Debt
Securities and of transfers and exchanges of the Debt Securities.  The Paying
Agent is hereby appointed  "Security Registrar" for the purpose of registering
the Debt Securities and  registering transfers and exchanges of the Debt
Securities as herein provided.

                 Upon surrender for registration of transfer of any Debt
Security of any series at the office or agency of the Company maintained for
such purpose, the Company or the Security Registrar shall execute, and the
Trustee shall authenticate and deliver, in the name of the designated
transferee, one or more new Debt Securities of the same series of like
aggregate principal amount of such denominations as are authorized for Debt
Securities of such series and of a like Stated Maturity and with like terms and
conditions.

                 At the option of the Holder, Debt Securities of any series
(except Global Notes) may be exchanged for other Debt Securities of the same
series of like aggregate principal amount and of a like Stated Maturity and
with like terms and conditions, upon surrender of the Debt Securities to be
exchanged at such office or agency.  

                 Whenever any Debt Securities (including any temporary Debt
Securities or Global Notes) are surrendered for exchange, the Company shall 
execute, and the Trustee shall authenticate and deliver, the Debt Securities to
the Holders entitled to receive the same.
 
                 (b)      All Debt Securities issued upon any transfer or
exchange of Debt Securities shall be valid obligations of the Company,
evidencing the same debt, and entitled to the same benefits under this
Indenture, as the Debt Securities surrendered for such transfer or exchange.

                 Every Debt Security presented or surrendered for transfer or
exchange shall (if so required by the Company or the Paying Agent) be duly 
endorsed, or be accompanied by a written





                                       24

<PAGE>   30
instrument of transfer in form satisfactory to the Company and the Security 
Registrar, duly executed by the Holder thereof or his attorney duly authorized 
in writing.

                 No service charge will be made for any transfer or exchange of
Debt Securities except as provided in SECTION 306.  The Company may require
payment of a sum sufficient to cover any tax or other governmental charge that
may be imposed in connection with any registration, transfer or exchange of
Debt Securities, other than those expressly provided in this Indenture to be
made at the Company's own expense or without expense or without charge to the
Holders.

                 Neither the Security Registrar nor the Company shall be
required (i) to issue or register, the transfer or exchange of Debt Securities
of any series during a period beginning at the opening of business 15 days
before the day of the transmission of a notice of redemption of Debt Securities
of such series selected for redemption under SECTION 1204 and ending at the
close of business on the day of such transmission, or (ii) to register,
transfer or exchange any Debt Security so selected for redemption in whole or
in part, except the unredeemed portion of any Debt Security being redeemed in
part.

                 (c)     The Company shall enter into an appropriate agency 
agreement with any Person designated by the Company as Security Registrar or 
Paying Agent that is not a party to this Indenture, which agreement shall 
incorporate the provisions of the Trust Indenture Act and shall implement the 
provisions of this Indenture that relate to such Security Registrar or Paying 
Agent. Prior to the designation of any such Person, the Company shall, by 
written notice (which notice shall include the name and address of the
principal office of such Person), inform the Trustee of such designation.

SECTION 306.  MUTILATED, DESTROYED, LOST AND STOLEN DEBT SECURITIES.

                 If (i) any mutilated Debt Security is surrendered at the
office or agency of the Company or the Security Registrar maintained for
such purpose or (ii) the Company and the Trustee receive evidence to their
satisfaction of the destruction, loss or theft of any Debt Security, and there
is delivered to the Company and the Trustee such security or indemnity as may
be required by them to save each of them and any Paying Agent and any Security
Registrar harmless, and none of the Company, the Trustee or the Security
Registrar receives notice that such Debt Security has been acquired by a bona
fide purchaser, then the Company shall execute and upon Company Request the
Security Registrar shall authenticate and deliver, in exchange for or in lieu
of any such mutilated, destroyed, lost or stolen Debt Security, a new Debt
Security of the same series of like Stated Maturity and with like terms and
conditions and like principal amount, bearing a number not contemporaneously
Outstanding.

                 In case any such mutilated, destroyed, lost or stolen Debt
Security has become or is about to become due and payable, the Company in its
discretion may, instead of issuing a new Debt Security, pay the amount due on
such Debt Security in accordance with its terms.

                 Upon the issuance of any new Debt Security under this Section,
the Company may require the payment of a sum sufficient to cover any tax or
other governmental charge that may be imposed in respect thereto and any other
expenses (including the fees and expenses of the Security Registrar) connected 
therewith.

                 Every new Debt Security of any series issued pursuant to this
Section shall constitute an original additional contractual obligation of the
Company, whether or not the destroyed, lost or stolen Debt Security shall be at
any time enforceable by anyone, and shall be entitled to all the benefits of
this Indenture equally and proportionately with any and all other Debt
Securities of that series duly issued hereunder.





                                       25

<PAGE>   31
                 The provisions of this Section are exclusive and shall
preclude (to the extent lawful) all other rights and remedies with respect to
the replacement or payment of mutilated, destroyed, lost or stolen Debt
Securities.

SECTION 307.  PAYMENT OF INTEREST; INTEREST RIGHTS PRESERVED.

                 (a)      Interest on any Debt Security that is payable and is
punctually paid or duly provided for on any Interest Payment Date shall be paid
to the Person in whose name such Debt Security (or one or more Predecessor
Securities) is registered at the close of business on the Regular Record Date
for such interest notwithstanding the cancellation of such Debt Security upon
any transfer or exchange subsequent to the Regular Record Date.  Payment of
interest on Debt Securities shall be made at the offices of the Paying Agent or
Paying Agents specified pursuant to SECTION 301, by check mailed to the 
address of the Person entitled thereto as such address shall appear in the 
Security Register or, upon request of a Holder of $10,000,000 (or the
equivalent thereof with respect to the specified Currency applicable to Debt
Securities denominated in a Foreign Currency) or more in aggregate principal
amount of Debt Securities will be entitled to receive interest payments by wire
transfer of immediately available funds if appropriate wire transfer
instructions have been received in writing by the Paying Agent not less than 15
days prior to such Interest Payment Date. Such wire instructions, upon receipt
by the Paying Agent, shall remain in effect until revoked by such Holder.

                 (b)      Any interest on any Debt Security that is payable but
is not punctually paid or duly provided for on any Interest Payment Date
(herein called "Defaulted Interest") shall forthwith cease to be payable to the
Holder on the relevant Regular Record Date by virtue of his having been such
Holder, and such Defaulted Interest may be paid by the Company, at its election
in each case, as provided in clause (1) or (2) below:

                 (1)      The Company may elect to make payment of any 
        Defaulted Interest to the Persons in whose names such Debt Securities 
        (or their respective Predecessor Securities) are registered at the 
        close of business on a Special Record Date for the payment of such 
        Defaulted Interest, which shall be fixed in the following manner.  The 
        Company shall notify the Trustee and the Paying Agent in writing of the
        amount of Defaulted Interest proposed to be paid on each such Debt 
        Security and the date of the proposed payment, and at the same time the
        Company shall deposit with the Paying Agent an amount of money in the 
        Currency or Currency unit in which the Debt Securities of such series 
        are payable (except as otherwise specified pursuant to SECTIONS 301 or 
        310) equal to the aggregate amount proposed to be paid in respect of 
        such Defaulted Interest or shall make arrangements satisfactory to the
        Trustee and the Paying Agent for such deposit prior to the date of the
        proposed payment, such money when deposited to be held in trust for the
        benefit of the Persons entitled to such Defaulted Interest as in this
        clause provided.  Thereupon the Paying Agent shall fix a Special Record
        Date for the payment of such Defaulted Interest which date shall be not
        more than 15 days and not less than 10 days prior to the date of the
        Paying Agent proposed payment and not less than 10 days after the
        receipt by the Paying Agent of the notice of the proposed payment.  The
        Paying Agent shall promptly notify the Company and the Trustee of such
        Special Record Date and, in the name and at the expense of the Company,
        the Trustee shall cause notice of the proposed payment of such
        Defaulted Interest and the Special Record Date therefor to be mailed,
        first-class postage prepaid, to the Holders of such Debt Securities at
        their addresses as they appear in the Security Register, not less than
        10 days prior to such Special Record Date.  Notice of the proposed
        payment of such Defaulted Interest and the Special Record Date therefor
        having been mailed as aforesaid, such Defaulted Interest shall be paid
        by the Paying Agent to





                                       26

<PAGE>   32
         the Persons in whose names such Debt Securities (or their respective
         Predecessor Securities) are registered at the close of business on
         such Special Record Date and shall no longer be payable pursuant to
         the following clause (2).

                 (2)      The Company may make payment of any Defaulted
         Interest on Debt Securities in any other lawful manner not
         inconsistent with the requirements of any securities exchange on which
         such Debt Securities may be listed, and upon such notice as may be
         required by such exchange, if, after notice given by the Company to
         the Trustee of the proposed payment pursuant to this clause, such
         manner of payment shall be deemed practicable by the Trustee.

                 (c)      Subject to the foregoing provisions of this Section,
each Debt Security delivered under this Indenture upon transfer of or in
exchange for or in lieu of any other Debt Security shall carry the rights to
interest accrued and unpaid, and to accrue, which were carried by such other
Debt Security.

SECTION 308.  CANCELLATION.

                 Unless otherwise specified pursuant to SECTION 301 for Debt 
Securities of any series, all Debt Securities surrendered for payment, 
redemption, transfer, or exchange, if  surrendered to any Person other than the
Security Registrar, shall be  delivered to the Security Registrar.  All Debt
Securities so delivered shall  be promptly canceled by the Security Registrar. 
The Company may at any time  deliver to the Security Registrar for cancellation
any Debt Securities  previously authenticated and delivered hereunder that the
Company may have  acquired in any manner whatsoever, and all Debt Securities
so delivered shall be promptly  canceled by the Security Registrar.  No Debt
Securities shall be authenticated  in lieu of or in exchange for any Debt
Securities canceled as provided in this  Section, except as expressly permitted
by this Indenture.  All canceled Debt  Securities held by the Security
Registrar shall be destroyed by the Security  Registrar or held by the Security
Registrar in accordance with the Security  Registrar's standard retention
policy, and the Security Registrar shall  deliver a certificate to such effect
to the Company.  The acquisition of any  Debt Securities by the Company shall
not operate as a redemption or  satisfaction of the indebtedness represented
thereby unless and until such  Debt Securities are surrendered to the Security
Registrar for cancellation.

SECTION 309.  COMPUTATION OF INTEREST.

                 Except as otherwise specified pursuant to SECTION 301 for Debt
Securities of any series, interest on the Debt Securities of each series shall
be computed on the basis of a 360-day year of twelve 30-day months.

SECTION 310.  CURRENCY OF PAYMENTS IN RESPECT OF DEBT SECURITIES.

                 (a)      With respect to Debt Securities of any series not
permitting the election provided for in paragraph (b) below or the Holders of
which have not made the election





                                       27

<PAGE>   33
provided for in paragraph (b) below, except as provided in paragraph (d) below,
payment of the principal of (and premium, if any) and any interest on any Debt
Security of such series will be made in the Currency in which such Debt
Security is payable.

                 (b)      It may be provided pursuant to SECTION 301 with
respect to the Debt Securities of any series that Holders shall have the
option, subject to paragraphs (d) and (e) below, to receive payments of
principal of (and premium, if any) and any interest on such Debt Securities in
any of the Currencies that may be designated for such election by delivering to
the Paying Agent and the Exchange Rate Agent a written election, to be in form 
and substance satisfactory to the Paying Agent, not later than the close of
business on the Election Date immediately preceding the applicable payment
date.  If a Holder so elects to receive such payments in any such Currency,
such election will remain in effect for such Holder or any transferee of such
Holder until changed by such Holder or such transferee by written notice to the
Paying Agent and the Exchange Rate Agent (but any such change must be made
not later than the close of business on the Election Date immediately preceding
the next payment date to be effective for the payment to be made on such
payment date and no such change or election may be made with respect to
payments to be made on any Debt Security of such series with respect to which
an Event of Default has occurred or notice of redemption has been given by the
Company pursuant to ARTICLE TWELVE).  Any Holder of any such Debt Security who
shall not have delivered any such election to the Paying Agent and the 
Exchange Rate Agent by the close of business on the applicable Election Date
will be paid the amount due on the applicable payment date in the relevant
Currency as provided in paragraph (a) of this SECTION 310.

                 (c)      If the election referred to in paragraph (b) above
has been provided for pursuant to SECTION 301, then not later than the fourth
Business Day after the Election Date for each payment date, the Paying Agent 
and the Exchange Rate Agent will deliver to the Company a written notice
specifying, in the Currency in which each series of the Debt Securities are
payable, the respective aggregate amounts of principal of (and premium, if any)
and any interest on the Debt Securities to be paid on such payment date,
specifying the amounts so payable in respect of the Debt Securities as to which
the Holders of Debt Securities denominated in any Currency shall have elected
to be paid in another Currency as provided in paragraph (b) above.  If the
election referred to in paragraph (b) above has been provided for pursuant to
SECTION 301 and if at least one Holder has made such election, then, on the
second Business Day preceding each payment date, the Company will deliver to
the Paying Agent and the Exchange Rate Agent an Exchange Rate Officer's
Certificate in respect of the Currency payments to be made on such payment
date.  The Currency amount receivable by Holders of Debt Securities who have
elected payment in a Currency as provided in paragraph (b) above shall be
determined by the Company on the basis of the applicable Market Exchange Rate
in effect on the third Business Day (the "Valuation Date") immediately
preceding each payment date.

                 (d)      If a Conversion Event occurs with respect to a
Foreign Currency, the ECU or any other Currency unit in which any of the Debt
Securities are denominated or payable other than pursuant to an election
provided for pursuant to paragraph (b) above, then with respect to each date
for the payment of principal of (and premium, if any) and any interest on the
applicable Foreign Currency, the ECU or such other Currency unit occurring
after the last date





                                       28

<PAGE>   34
on which such Foreign Currency, the ECU or such other Currency unit was used
(the "Conversion Date"), the Dollar shall be the Currency of payment for use on
each such payment date.  The Dollar amount to be paid by the Company to the
Paying Agent and by the Paying Agent to the Holders of such Debt
Securities with respect to such payment date shall be the Dollar Equivalent of
the Foreign Currency or, in the case of a Currency unit, the Dollar Equivalent
of the Currency unit, in each case as determined by the Exchange Rate 
Agent in the manner provided in paragraph (f) or (g) below.

                 (e)      If the Holder of a Debt Security denominated in any
Currency shall have elected to be paid in another Currency as provided in
paragraph (b) above, and a Conversion Event occurs with respect to such elected
Currency, such Holder shall receive payment in the Currency in which payment
would have been made in the absence of such election.  If a Conversion Event
occurs with respect to the Currency in which payment would have been made in
the absence of such election, such Holder shall receive payment in Dollars as
provided in paragraph (d) of this SECTION 310.

                 (f)      The "Dollar Equivalent of the Foreign Currency" shall
be determined by the Exchange Rate Agent and shall be obtained for
each subsequent payment date by converting the specified Foreign Currency into
Dollars at the Market Exchange Rate on the Conversion Date.

                 (g)      The "Dollar Equivalent of the Currency Unit" shall be
determined by the Exchange Rate Agent and subject to the provisions of
paragraph (h) below, shall be the sum of each amount obtained by converting the
Specified Amount of each Component Currency into Dollars at the Market Exchange
Rate for such Component Currency on the Valuation Date with respect to each
payment.

                 (h)      For purposes of this SECTION 310 the following terms
shall have the following meanings:

                 A "Component Currency" shall mean any Currency which, on the
Conversion Date, was a component currency of the relevant Currency unit,
including, but not limited to, the ECU.

                 A "Specified Amount" of a Component Currency shall mean the
number of units of such Component Currency or fractions thereof which were
represented in the relevant currency unit, including, but not limited to, the
ECU, on the Conversion Date.  If after the Conversion Date the official unit of
any Component Currency is altered by way of combination or subdivision, the
Specified Amount of such Component Currency shall be divided or multiplied in
the same proportion.  If after the Conversion Date two or more Component
Currencies are consolidated into a single Currency, the respective Specified
Amounts of such Component Currencies shall be replaced by an amount in such
single Currency equal to the sum of the respective Specified Amounts of such
consolidated Component Currencies expressed in such single Currency, and such
amount shall thereafter be a Specified Amount and such single Currency shall
thereafter be a Component Currency.  If after the Conversion Date any





                                       29

<PAGE>   35
Component Currency shall be divided into two or more Currencies, the Specified
Amount of such Component Currency shall be replaced by amounts of such two or
more Currencies with appropriate Dollar equivalents at the Market Exchange Rate
on the date of such replacement equal to the dollar equivalent of the Specified
Amount of such former Component Currency at the Market Exchange Rate on such
date, and such amounts shall thereafter be Specified Amounts and such
Currencies shall thereafter be Component Currencies.  If after the Conversion
Date of the relevant Currency unit, including but not limited to, the ECU, a
Conversion Event (other than any event referred to above in this definition of
"Specified Amount") occurs with respect to any Component Currency of such
Currency unit, the Specified Amount of such Component Currency shall, for
purposes of calculating the Dollar Equivalent of the Currency unit, be
converted into Dollars at the Market Exchange Rate in effect on the Conversion
Date of such Component Currency.

                 "Election Date" shall mean the record date with respect to any
Stated Maturities, and with respect to the Maturity shall mean the record date
(if within 16 or fewer days prior to the Maturity) immediately preceding the
Maturity, and with respect to any series of Debt Securities whose record date
immediately preceding the Maturity is more than 16 days prior to the Maturity
or any series of Debt Securities for which no record dates are provided with
respect to the Stated Maturities or the Maturity shall mean the date that is
16 days prior to the Stated Maturity or the Maturity, as the case may be.
        
                 (i)      All decisions and determinations of the Exchange 
Rate Agent regarding the Dollar Equivalent of the Foreign Currency, the Dollar 
Equivalent of the Currency Unit and the Market Exchange Rate shall be in its
sole discretion and shall, in the absence of manifest error, be conclusive for
all purposes and irrevocably binding upon the Company and all Holders of the
Debt Securities denominated or payable in the relevant Currency.  In the event
of a Conversion Event with respect to a Foreign Currency, the Company, after
learning thereof, will immediately give written notice thereof to the Trustee,
the Paying Agent and the Exchange Rate Agent (and the Trustee will promptly
thereafter give notice in the manner provided in SECTION 105 to the Holders of
the relevant Debt Securities) specifying the Conversion Date.  In the event of
a Conversion Event with respect to the ECU or any other Currency unit in which
Securities are denominated or payable, the Company, after learning thereof,
will immediately give notice thereof to the Trustee, the Paying Agent and the
Exchange Rate Agent (and the Trustee will promptly thereafter give written
notice in the manner provided in SECTION 105 to the Holders) specifying the
Conversion Date and the Specified Amount of each Component Currency on the
Conversion Date.  In the event of any subsequent change in any Component
Currency as set forth in the definition of Specified Amount above, the Company,
after learning thereof, will similarly give written notice to the Trustee, the
Paying Agent and the Exchange Rate Agent.  The Trustee and the Paying Agent
shall be fully justified and protected in relying and acting upon information
received by it from the Company and the Exchange Rate Agent and shall not
otherwise have any duty or obligation to determine such information
independently.






                                       30

<PAGE>   36
SECTION 311.  JUDGMENTS.

                 If for the purpose of obtaining a judgment in any court with
respect to any obligation of the Company hereunder or under any Debt Security,
it shall become necessary to convert into any other Currency any amount in the
Currency due hereunder or under such Debt Security, then such conversion shall
be made at the Market Exchange Rate as in effect on the date the Company shall
make payment to any Person in satisfaction of such judgment.  If pursuant to
any such judgment, conversion shall be made on a date other than the date
payment is made and there shall occur a change between such Market Exchange
Rate and the Market Exchange Rate as in effect on the date of payment, the
Company agrees to pay such additional amounts (if any) as may be necessary to
ensure that the amount paid is equal to the amount in such other Currency
which, when converted at the Market Exchange Rate as in effect on the date of
payment or distribution, is the amount then due hereunder or under such Debt
Security.  Any amount due from the Company under this SECTION 311 shall be due
as a separate debt and is not to be affected by or merged into any judgment
being obtained for any other sums due hereunder or in respect of any Debt
Security.  In no event, however, shall the Company be required to pay more in
the Currency or Currency unit due hereunder or under such Debt Security at the
Market Exchange Rate as in effect when payment is made than the amount of
Currency stated to be due hereunder or under such Debt Security so that in any
event the Company's obligations hereunder or under such Debt Security will be
effectively maintained as obligations in such Currency, and the Company shall
be entitled to withhold (or be reimbursed for, as the case may be) any excess
of the amount actually realized upon any such conversion over the amount due
and payable on the date of payment or distribution.


                                  ARTICLE FOUR

                           SATISFACTION AND DISCHARGE

SECTION 401.  SATISFACTION AND DISCHARGE OF INDENTURE.

                 This Indenture, with respect to the Debt Securities of any
series (if all series issued under this Indenture are not to be affected),
shall, upon Company Request, cease to be of further effect (except as to any
surviving rights of registration of transfer or exchange of such Debt
Securities herein expressly provided for and rights to receive payments of
principal (and premium, if any) and interest on such Debt Securities) and the
Trustee, at the expense of the Company, shall execute proper instruments
acknowledging satisfaction and discharge of this Indenture, when





                                       31

<PAGE>   37
         (1)      either

                 (A)      all Debt Securities of such series theretofore
         authenticated and delivered (other than (i) Debt Securities of such
         series which have been destroyed, lost or stolen and which have been
         replaced or paid as provided in SECTION 306 and (ii) Debt Securities
         of such series for whose payment money has theretofore been deposited
         in trust or segregated and held in trust by the Company and thereafter
         repaid to the Company or discharged from such trust, as provided in
         SECTION 1103) have been delivered to the Security Registrar for 
         cancellation; or

                 (B)      all Debt Securities of such series not theretofore
         delivered to the Security Registrar for cancellation,
         
                      (i)         have become due and payable; or

                     (ii)         will become due and payable at their Stated 
                 Maturity within one year; or

                    (iii)         are to be called for redemption within one
                 year under arrangements satisfactory to the Trustee for the
                 giving of notice by the Trustee in the name, and at the
                 expense, of the Company,

         and the Company, in the case of (i), (ii) or (iii) of this subclause
         (B), has irrevocably deposited or caused to be deposited with the
         Trustee as trust funds in trust for such purpose an amount in the
         Currency in which such Debt Securities are denominated (except as
         otherwise provided pursuant to SECTIONS 301 or 310), sufficient to pay
         and discharge the entire indebtedness on such Debt Securities for
         principal (and premium, if any) and interest to the date of such
         deposit (in the case of Debt Securities which have become due and
         payable) or to the Stated Maturity or Redemption Date, as the case may
         be; provided, however, in the event a petition for relief under the
         federal bankruptcy laws, as now or hereafter constituted, or any other
         applicable federal or state bankruptcy, insolvency or other similar
         law, is filed with respect to the Company within 91 days after the
         deposit and the Trustee is required to return the deposited money to
         the Company, the obligations of the Company under this Indenture with
         respect to such Debt Securities shall not be deemed terminated or
         discharged;

         (2)      the Company has paid or caused to be paid all other sums
payable hereunder by the Company; and

         (3)      the Company has delivered to the Trustee an Officers'
Certificate and an Opinion of Counsel each stating that all conditions
precedent herein provided for relating to the satisfaction and discharge of
this Indenture with respect to such series have been complied with.

Notwithstanding the satisfaction and discharge of this Indenture, the
obligations of the Company to the Trustee under SECTION 607, the obligations of
the Trustee to any Authenticating Agent





                                       32

<PAGE>   38
under SECTION 611 and, if money shall have been deposited with the Trustee
pursuant to subclause (B) of clause (1) of this Section, the obligations of the
Trustee under SECTION 402 and the last paragraph of SECTION 1103 shall survive.
If, after the deposit referred to in this SECTION 401 has been made, (x) the
Holder of a Debt Security is entitled to, and does, elect pursuant to SECTION
310(B), to receive payment in a Currency other than that in which the deposit
pursuant to this SECTION 401 was made, or (y) if a Conversion Event occurs with
respect to the Currency in which the deposit was made or elected to be received
by the Holder pursuant to SECTION 310(B), then the indebtedness represented by
such Debt Security shall be fully discharged to the extent that the deposit
made with respect to such Debt Security shall be converted into the Currency in
which such payment is made.

SECTION 402.  APPLICATION OF TRUST MONEY.

                 Subject to the provisions of the last paragraph of SECTION
1103, all money deposited with the Trustee pursuant to SECTION 401 shall be
held in trust and applied by it, in accordance with the provisions of the Debt
Securities and this Indenture, to the payment, either directly or through any
Paying Agent (including the Company acting as its own Paying Agent) as the
Trustee may determine, to the Persons entitled thereto, of the principal (and
premium, if any) and interest for whose payment such money has been deposited
with the Trustee.


                                  ARTICLE FIVE

                                    REMEDIES

SECTION 501.  EVENTS OF DEFAULT.

                 "Event of Default" wherever used herein with respect to Debt
Securities of any series means any one of the following events (whatever the
reason for such Event of Default and whether it shall be voluntary or
involuntary or be effected by operation of law, pursuant to any judgment,
decree or order of any court or any order, rule or regulation of any
administrative or governmental body):

                 (1)      default in the payment of any interest upon any Debt
         Security of such series when it becomes due and payable, and
         continuance of such default for a period of 30 days; or

                 (2)      default in the payment of the principal of (or
         premium, if any, on) any Debt Security of such series at its Maturity;
         or

                 (3)      default in the performance, or breach, of any
         covenant or warranty of the Company in this Indenture (other than a
         covenant or warranty a default in whose performance or whose breach is
         elsewhere in this Section specifically dealt with or which expressly
         has been included in this Indenture solely for the benefit of Debt
         Securities of a series other than such series), and continuance of
         such default or breach for a period





                                       33

<PAGE>   39
         of 60 days after there has been given, by registered or certified
         mail, to the Company by the Trustee or to the Company and the Trustee
         by the Holders of at least 10% in principal amount of the Outstanding
         Debt Securities of such series, a written notice specifying such
         default or breach and requiring it to be remedied and stating that
         such notice is a "Notice of Default" hereunder; or

                 (4)       the entry of a decree or order for relief in respect
         of the Company or any Significant Subsidiary by a court having 
         jurisdiction in the premises in an involuntary case or proceeding 
         under the federal bankruptcy laws, as now or hereafter constituted, 
         or any other applicable federal or state bankruptcy, insolvency, 
         reorganization or other similar law, or a decree or order adjudging 
         the Company or any Significant Subsidiary bankrupt or insolvent, or
         approving as properly filed a petition seeking reorganization,
         arrangement, adjustment or composition of or in respect of the Company
         or any Significant Subsidiary under any applicable federal or state 
         law, or appointing a receiver, liquidator, assignee, custodian, 
         trustee, sequestrator (or other similar official) of the Company or 
         of any substantial part of the property of the Company or any 
         Significant Subsidiary, or ordering the winding up or liquidation of 
         its affairs, and the continuance of any such decree or order 
         unstayed and in effect for a period of 60 consecutive days; or

                 (5)       the commencement by the Company or any Significant
         Subsidary of a voluntary case or proceeding under the federal 
         bankruptcy laws, as now or hereafter constituted, or any other 
         applicable federal or state bankruptcy, insolvency, reorganization 
         or other similar law, or the consent by it to the entry of an order 
         for relief in an involuntary case under any such law or to the 
         appointment of a receiver, liquidator, assignee, custodian, trustee, 
         sequestrator (or other similar official) of the Company or any 
         Significant Subsidiary or of any substantial part of the property of 
         the Company or any Significant Subsidiary, or the making by the
         Company or any Significant Subsidiary of an assignment for the 
         benefit of its creditors, or the admission by the Company or any 
         Significant Subsidiary in writing of its inability to pay its debts 
         generally as they become due, or the taking of corporate action by 
         the Company or any Significant Subsidiary in furtherance of any 
         such action; or

                 (6)      failure to pay at final maturity or upon the 
         declaration of acceleration of payments of indebtedness for borrowed 
         money of the Company or any Significant Subsidiary aggregating in 
         excess of $5,000,000 (whether such indebtedness now exists or is 
         hereafter created) as a result of the occurrence of one or more 
         events of default as defined in any mortgages, indentures or 
         instruments under which such indebtedness shall have been issued or 
         by which such indebtedness shall have been secured, and such failure 
         to pay shall not be cured or such acceleration or accelerations, as 
         the case may be, shall not be rescinded, annulled or cured, in any 
         such case prior to the expiration of 30 days after the date such 
         failure to pay or acceleration or accelerations shall have occurred; or

                 (7)       any other Event of Default provided with respect to
         Debt Securities of that series pursuant to SECTION 301.





                                       34

<PAGE>   40
SECTION 502. ACCELERATION OF MATURITY; RESCISSION AND ANNULMENT.

                 If an Event of Default with respect to Debt Securities of any
series at the time Outstanding (other than an Event of Default specified in
Section 501(4) or Section 501(5) with respect to the Company) occurs and is
continuing, then in every such case the Trustee or the Holders of not less than
25% in principal amount of Outstanding Debt Securities of such series may
declare the principal amount (or, if any Debt Securities of such series are
Discount Securities, such portion of the principal amount of such Discount
Securities as may be specified in the terms of such Discount Securities) of all
the Debt Securities of such series to be due and payable immediately, by a
notice in writing to the Company (and to the Trustee if given by Holders), and
upon any such declaration such principal amount (or specified amount), together
with accrued and unpaid interest thereon, shall become immediately due and 
payable, without presentment, demand, protest, notice of intent to accelerate 
or other notice of any kind (except as otherwise provided in this Indenture), 
all of which are hereby waived. If an Event of Default specified in Section 
501(4) or Section 501(5) occurs and is continuing with respect to the Company,
then the principal amount (or, if any Debt Securities of such series are
Discount Securities, such portion of the principal amount of such Discount
Securities as may be specified in the terms of such Discount Securities),
together with accrued and unpaid interest thereon, of all the Debt Securities
of  such series shall ipso facto become and be immediately due and payable,
without presentment, demand, protest, notice of intent to accelerate or other
notice of any kind (except as otherwise provided in this Indenture), all of
which are hereby waived, and without any declaration or other act on the part
of the Trustee or any Holder.  Upon payment of such amount in the Currency in
which such Debt Securities are denominated (except as otherwise provided
pursuant to SECTIONS 301 or 310), all obligations of the Company in respect of
the payment of principal of the Debt Securities of such series shall terminate.
        
                 At any time after such a declaration of acceleration with
respect to Debt Securities of any series has been made and before a judgment or
decree for payment of the money due has been obtained by the Trustee as
hereinafter in this Article provided, the Holders of a majority in principal
amount of the Outstanding Debt Securities of such series, by written notice to
the Company and the Trustee, may rescind and annul such declaration and its
consequences if:

                 (1)       the Company has paid or deposited with the Trustee a
         sum in the Currency in which such Debt Securities are denominated
         (except as otherwise provided pursuant to SECTIONS 301 or 310)
         sufficient to pay

                          (A)      all overdue installments of interest on all
                 Debt Securities of such series;

                          (B)      the principal of (and premium, if any, on)
                 any Debt Securities of such series which have become due
                 otherwise than by such declaration of acceleration and
                 interest thereon at the rate or rates prescribed therefor in
                 such Debt Securities;

                          (C)      to the extent that payment of such interest
                 is lawful, interest upon overdue installments of interest on
                 each Debt Security at the Overdue Rate; and

                          (D)      all sums paid or advanced by the Trustee
                 hereunder and the reasonable compensation, expenses,
                 disbursements and advances of the Trustee, its agents and
                 counsel; provided, however, that all sums payable under this
                 clause (D) shall be paid in Dollars;

         and

                 (2)       all Events of Default with respect to Debt
         Securities of such series, other than the nonpayment of the principal
         of Debt Securities of such series which have





                                       35

<PAGE>   41
         become due solely by such declaration of acceleration, have been cured
         or waived as provided in SECTION 513.

No such rescission and waiver shall affect any subsequent default or impair any
right consequent thereon.

SECTION 503. COLLECTION OF INDEBTEDNESS AND SUITS FOR ENFORCEMENT BY TRUSTEE.

                 The Company covenants that if:

                 (1)      default is made in the payment of any installment of
         interest on any Debt Security when such interest becomes due and
         payable and such default continues for a period of 30 days; or

                 (2)      default is made in the payment of principal of (or
         premium, if any, on) any Debt Security at the Maturity thereof; 


the Company will, upon demand of the Trustee, pay to it, for the benefit of the
Holders of such Debt Securities the amount then due and payable on such Debt
Securities for the principal (and premium, if any) and interest, if any, and,
to the extent that payment of such interest shall be legally enforceable,
interest upon the overdue principal (and premium, if any) and upon overdue
installments of interest, at the Overdue Rate; and, in addition thereto, such
further amount as shall be sufficient to cover the costs and expenses of
collection, including the reasonable compensation, expenses, disbursements and
advances of the Trustee, its agents and counsel.

                 If the Company fails to pay such amount forthwith upon such
demand, the Trustee, in its own name and as trustee of an express trust, may
institute a judicial proceeding for the collection of the sums so due and
unpaid, and may prosecute such proceeding to judgment or final decree, and may
enforce the same against the Company or any other obligor upon such Debt
Securities, and collect the moneys adjudged or decreed to be payable in the
manner provided by law out of the property of the Company or any other obligor
upon such Debt Securities wherever situated.

                 If an Event of Default with respect to Debt Securities of any
series occurs and is continuing, the Trustee may in its discretion proceed to
protect and enforce its rights and the rights of the Holders of Debt Securities
of such series by such appropriate judicial proceedings as the Trustee shall
deem most effectual to protect and enforce any such rights, whether for the
specific enforcement of any covenant or agreement in this Indenture or in aid
of the exercise of any power granted herein, or to enforce any other proper
remedy.





                                       36

<PAGE>   42
SECTION 504.  TRUSTEE MAY FILE PROOFS OF CLAIM.

                 In case of the pendency of any receivership, insolvency,
liquidation, bankruptcy, reorganization, arrangement, adjustment, composition
or other judicial proceedings, or any voluntary or involuntary case under the
federal bankruptcy laws, as now or hereafter constituted, relative to the
Company or any other obligor upon the Debt Securities, if any, of a particular
series or the property of the Company or of such other obligor or their
creditors, the Trustee (irrespective of whether the principal of such Debt
Securities shall then be due and payable as therein expressed or by declaration
of acceleration or otherwise and irrespective of whether the Trustee shall have
made any demand on the Company for the payment of overdue principal or
interest) shall be entitled and empowered, by intervention in such proceeding
or otherwise:

              (i)         to file and prove a claim for the whole amount of
         principal (or, if the Debt Securities of such series are Discount
         Securities, such portion of the principal amount as may be due and
         payable with respect to such series pursuant to a declaration in
         accordance with SECTION 502) (and premium, if any) and interest owing
         and unpaid in respect of the Debt Securities of such series and to
         file such other papers or documents as may be necessary or advisable
         in order to have the claims of the Trustee (including any claim for
         the reasonable compensation, expenses, disbursements and advances of
         the Trustee, its agents and counsel) and of the Holders of such Debt
         Securities allowed in such judicial proceeding; and

             (ii)         to collect and receive any moneys or other property
         payable or deliverable on any such claims and to distribute the same;

and any receiver, assignee, trustee, custodian, liquidator, sequestrator or
other similar official in any such proceeding is hereby authorized by each such
Holder to make such payments to the Trustee, and in the event that the Trustee
shall consent to the making of such payments directly to such Holders, to pay
to the Trustee any amount due it for the reasonable compensation, expenses,
disbursements and advances of the Trustee, its agents and counsel, and any
other amounts due the Trustee under SECTION 607.

                 Nothing herein contained shall be deemed to authorize the
Trustee to authorize or consent to or accept or adopt on behalf of any Holder
any plan of reorganization, arrangement, adjustment or composition affecting
the Debt Securities of such series or the rights of any Holder thereof, or to
authorize the Trustee to vote in respect of the claim of any Holder in any such
proceeding.

SECTION 505. TRUSTEE MAY ENFORCE CLAIMS WITHOUT POSSESSION OF DEBT SECURITIES.

                 All rights of action and claims under this Indenture or the
Debt Securities of any series may be prosecuted and enforced by the Trustee
without the possession of any of such Debt Securities or the production thereof
in any proceeding relating thereto, and any such proceeding instituted by the
Trustee shall be brought in its own name, as trustee of an express trust, and
any recovery of judgment shall, after provision for the payment of the
reasonable compensation,





                                       37

<PAGE>   43
expenses, disbursements and advances of the Trustee, its agents and counsel, be
for the ratable benefit of the Holders of the Debt Securities in respect of
which such judgment has been recovered.

SECTION 506.  APPLICATION OF MONEY COLLECTED.

                 Any money collected by the Trustee pursuant to this Article 
shall be applied in the following order, at the date or dates fixed by the
Trustee and, in case of the distribution of such money on account of principal
(and premium, if any) or interest, upon presentation of the Debt Securities of
any series in respect of which money has been collected and the notation
thereon of the payment if only partially paid and upon surrender thereof if
fully paid:
        
                 FIRST: To the payment of all amounts due the Trustee under
         SECTION 607;

                 SECOND: To the payment of the amounts then due and unpaid for
         interest on the Debt Securities and any Defaulted Interest and any
         interest payable thereon, and principal of (and premium, if any) on 
         the Debt Securities of such series, in respect of which or for the 
         benefit of which such money has been collected ratably, without 
         preference or priority of any kind, according to the amounts due and 
         payable on such Debt Securities for principal (and premium, 
         if any), interest and Defaulted Interest, respectively; and

                 THIRD:  The balance, if any, to the Company or as a court of
         competent jurisdiction may otherwise direct.

                 In any case where Debt Securities are outstanding which are
denominated in more than one Currency, or in a Component Currency, and the
Trustee is directed to make ratable payments under this section to Holders of
such Debt Securities, the Trustee shall calculate the amount of such payments
as follows: (i) as of the date the Trustee collects an amount under this
Article, the Trustee shall, as to each Holder of a Debt Security to whom an
amount is due and payable under this Section which is denominated in a Foreign
Currency or a Component Currency, determine that amount of Dollars that would
be obtained for the amount owing such Holder, using the rate of exchange at
which in accordance with normal banking procedures the Trustee could purchase
in The City of New York Dollars with such amount owing; (ii) calculate the sum
of all Dollar amounts determined under (i) and add thereto any amounts due and
payable in Dollars; and (iii) using the individual amounts determined in (i) or
any individual amounts due and payable in Dollars, as the case may be, as a
numerator and the sum calculated in (ii) as a denominator, calculate as to each
Holder of a Debt Security to whom an amount is owed under this Section the
fraction of the amount collected under this Article payable to such Holder.
Any expenses incurred by the Trustee in actually converting amounts owing
Holders of Debt Securities denominated in a Currency or a Component Currency
other than that in which any amount is collected under this ARTICLE FIVE shall
likewise be (in accordance with this paragraph) borne ratably by any Holders of
Debt Securities denominated in a Currency or a Component Currency other than
that in which any amount is collected under this ARTICLE FIVE.




                                       38

<PAGE>   44
SECTION 507.  LIMITATION ON SUITS.

                 No Holder of any Debt Security of any series shall have any
right to institute any proceeding, judicial or otherwise, with respect to this
Indenture, or for the appointment of a receiver or trustee, or for any other
remedy hereunder, unless:

                 (1)       such Holder has previously given written notice to
         the Trustee of a continuing Event of Default with respect to such
         series;

                 (2)       the Holders of not less than 25% in principal amount
         of the Outstanding Debt Securities of such series shall have made
         written request to the Trustee to institute proceedings in respect of
         such Event of Default in its own name as Trustee hereunder;

                 (3)       such Holder or Holders have offered to the Trustee
         reasonable indemnity against the costs, expenses and liabilities to be
         incurred in compliance with such request;

                 (4)       the Trustee for 60 days after its receipt of such
         notice, request and offer of indemnity has failed to institute any
         such proceeding; and

                 (5)       no direction inconsistent with such written request
         has been given to the Trustee during such 60-day period by the Holders
         of a majority in principal amount of the Outstanding Debt Securities
         of such series;

it being understood and intended that no one or more of such Holders shall have
any right in any manner whatever by virtue of, or by availing of, any provision
of this Indenture to affect, disturb or prejudice the rights of any other such
Holders or of the Holders of Outstanding Debt Securities of any other series,
or to obtain or to seek to obtain priority or preference over any other of such
Holders or to enforce any right under this Indenture, except in the manner
herein provided and for the equal and ratable benefit of all of such Holders.
For the protection and enforcement of the provisions of this SECTION 507, each
and every Holder of Debt Securities of any series and the Trustee for such
series shall be entitled to such relief as can be given at law or in equity.

SECTION 508. UNCONDITIONAL RIGHT OF HOLDERS TO RECEIVE PRINCIPAL, PREMIUM AND
INTEREST.

                 Notwithstanding any other provision in this Indenture, the
Holder of any Debt Security shall have the right, which is absolute and
unconditional, to receive payment of the principal of (and premium, if any) and
(subject to SECTION 115 and SECTION 307) interest on such Debt Security on the
respective Stated Maturity or Maturities expressed in such Debt Security (or,
in the case of redemption, on the Redemption Date) and to institute suit for
the enforcement of any such payment and interest thereon, and such right shall
not be impaired without the consent of such Holder.





                                       39

<PAGE>   45
SECTION 509.  RESTORATION OF RIGHTS AND REMEDIES.

                 If the Trustee or any Holder has instituted any proceeding to
enforce any right or remedy under this Indenture and such proceeding has been
discontinued or abandoned for any reason, or has been determined adversely to
the Trustee or to such Holder, then and in every such case the Company, the
Trustee and the Holders shall, subject to any determination in such proceeding,
be restored severally and respectively to their former positions hereunder, and
thereafter all rights and remedies of the Trustee and the Holders shall
continue as though no such proceeding had been instituted.

SECTION 510.  RIGHTS AND REMEDIES CUMULATIVE.

                 Except as otherwise expressly provided elsewhere in this
Indenture, no right or remedy herein conferred upon or reserved to the Trustee
or to the Holders is intended to be exclusive of any other right or remedy, and
every right and remedy shall, to the extent permitted by law, be cumulative and
in addition to every other right and remedy given hereunder or now or hereafter
existing at law or in equity or otherwise.  The assertion or employment of any
right or remedy hereunder, or otherwise, shall not prevent the concurrent
assertion or employment of any other appropriate right or remedy.

SECTION 511.  DELAY OR OMISSION NOT WAIVER.

                 No delay or omission of the Trustee or of any Holder to
exercise any right or remedy accruing upon any Event of Default shall impair
any such right or remedy or constitute a waiver of any such Event of Default or
any acquiescence therein.  Every right and remedy given by this Indenture or by
law to the Trustee or to the Holders may be exercised from time to time, and as
often as may be deemed expedient, by the Trustee or by the Holders, as the case
may be.

SECTION 512.  CONTROL BY HOLDERS.

                 Subject to Section 701, the Holders of a majority in principal 
amount of the Outstanding Debt Securities of any series shall have the right to 
direct the time, method and place of conducting any proceeding for any remedy 
available to the Trustee or exercising any trust or power conferred on the 
Trustee with respect to the Debt Securities of such series, provided, that

                 (1)      such direction shall not be in conflict with any rule
         of law or with this Indenture;

                 (2)      subject to any incorporated provisions, the Trustee
         shall have the right to decline to follow any such direction if the
         Trustee in good faith shall, by a Responsible Officer or Responsible
         Officers of the Trustee, determine that the proceeding so directed
         would be unjustly prejudicial to the Holders of Debt Securities of
         such series not joining in any such direction; and





                                       40

<PAGE>   46
                 (3)      the Trustee may take any other action deemed proper
         by the Trustee that is not inconsistent with such direction.

SECTION 513. WAIVER OF PAST DEFAULTS.

                 The Holders of not less than a majority in principal amount of
the Outstanding Debt Securities of any series may on behalf of the Holders of
all the Debt Securities of any such series waive any past default hereunder
with respect to such series and its consequences, except a default

                 (1)       in the payment of any interest upon any Debt 
         Security of such series when it becomes due and payable, or

                 (2)      in the payment of the principal of (or premium, if
         any, on) any Debt Security of such series at its Maturity; or

                 (3)      in respect of a covenant or provision hereof which
         pursuant to ARTICLE TEN cannot be modified or amended without the
         consent of the Holder of each outstanding Debt Security of such series
         affected.

                 Upon any such waiver, such default shall cease to exist, and
any Event of Default arising therefrom shall be deemed to have been cured, for
every purpose of the Debt Securities of such series under this Indenture; but
no such waiver shall extend to any subsequent or other default or impair any
right consequent thereon.

SECTION 514.  UNDERTAKING FOR COSTS.

                 All parties to this Indenture agree, and each Holder of any
Debt Security by his acceptance thereof shall be deemed to have agreed, that
any court may in its discretion require, in any suit for the enforcement of any
right or remedy under this Indenture, or in any suit against the Trustee for
any action taken, suffered or omitted by it as Trustee, the filing by any party
litigant in such suit other than the Trustee of an undertaking to pay the costs
of such suit, and that such court may in its discretion assess reasonable
costs, including reasonable attorneys' fees, against any party litigant in such
suit, having due regard to the merits and good faith of the claims or defenses
made by such party litigant; but the provisions of this Section shall not apply
to any suit instituted by the Trustee, to any suit instituted by any Holder or
group of Holders holding in the aggregate more than 10% in principal amount of
the Outstanding Debt Securities of any series, or to any suit instituted by any
Holder of a Debt Security for the enforcement of the payment of the principal
of (or premium, if any) or interest on such Debt Security on or after the
respective Stated Maturity or Maturities expressed in such Debt Security (or,
in the case of redemption, on or after the Redemption Date).

SECTION 515.  WAIVER OF STAY OR EXTENSION LAWS.

                 The Company covenants (to the extent that it may lawfully do
so) that it will not at any time insist upon, or plead, or in any manner
whatsoever claim or take the benefit or advantage of, any stay or extension law
wherever enacted, now or at any time hereafter in force,





                                       41

<PAGE>   47
which may affect the covenants or the performance of this Indenture; and the
Company (to the extent that it may lawfully do so) hereby expressly waives all
benefit or advantage of any such law, and covenants that it will not hinder,
delay or impede the execution of any power herein granted to the Trustee, but
will suffer and permit the execution of every such power as though no such law
had been enacted.


                                  ARTICLE SIX

                                  THE TRUSTEE

SECTION 601.  CERTAIN DUTIES AND RESPONSIBILITIES.

                 (a)      Except during the continuance of an Event of Default
with respect to the Debt Securities of any series,

                 (1)      the Trustee undertakes to perform such duties as are
         specifically set forth in this Indenture, and no implied covenants or
         obligations shall be read into this Indenture against the Trustee; and

                 (2)      in the absence of bad faith on its part, the Trustee
         may conclusively rely, as to the truth of the statements and the
         correctness of the opinions expressed therein, upon certificates or
         opinions furnished to the Trustee and conforming to the requirements
         of this Indenture; but in the case of any such statements, 
         certificates or opinions which by any provisions hereof are 
         specifically required to be furnished to the Trustee, the Trustee 
         shall be under a duty to examine the same to determine whether they 
         conform to the requirements of this Indenture.

                 (b)      In case an Event of Default with respect to Debt
Securities of any series has occurred and is continuing, the Trustee shall,
with respect to the Debt Securities of such series, exercise such of the rights
and powers vested in it by this Indenture, and use the same degree of care and
skill in their exercise, as a prudent man would exercise or use under the
circumstances in the conduct of his own affairs.

                 (c) No provision of this Indenture shall be construed to
relieve the Trustee from liability for its own negligent action, its own
negligent failure to act or its own willful misconduct, provided that

                 (1)      this subsection shall not be construed to limit the
         effect of subsection (a) of this Section;

                 (2)      the Trustee shall not be liable for any error of
         judgment made in good faith by a Responsible Officer, unless it shall
         be proved that the Trustee was negligent in ascertaining the pertinent
         facts;





                                       42

<PAGE>   48
                 (3)      the Trustee shall not be liable with respect to any
         action taken, suffered or omitted to be taken by it with respect to
         Debt Securities of any series in good faith and believed by it to be
         authorized or within the discretion, rights or powers conferred upon
         it hereby, or in accordance with the direction of the Holders of a
         majority in principal amount of the Outstanding Debt Securities of
         such series relating to the time, method and place of conducting any
         proceeding for any remedy available to the Trustee, or exercising any
         trust or power conferred upon the Trustee, under this Indenture; and

                 (4)      the Trustee shall not be required to expend or risk
         its own funds or otherwise incur any financial liability in the
         performance of any of its duties hereunder, or in the exercise of any
         of its rights or powers, if it shall have reasonable grounds for
         believing that repayment of such funds or adequate indemnity against
         such risk or liability is not reasonably assured to it.

                 (d)      Whether or not therein expressly so provided, every
provision of this Indenture relating to the conduct or affecting the liability
of or affording protection to the Trustee shall be subject to the provisions of
this Section.

SECTION 602.  NOTICE OF DEFAULTS.

                 Within 90 days after the occurrence of any default hereunder
with respect to Debt Securities of any series the Trustee shall give notice to
all Holders of Debt Securities of such series of such default hereunder known
to the Trustee, unless such default shall have been cured or waived; provided,
however, that, except in the case of a default in the payment of the principal
of (or premium, if any) or interest on any Debt Security of such series or in
the payment of any sinking fund installment with respect to Debt Securities of
such series, the Trustee shall be protected in withholding such notice if and
so long as the board of directors, the executive committee or a trust committee
of directors and/or Responsible Officers of the Trustee in good faith determine
that the withholding of such notice is in the interest of the Holders of Debt
Securities of such series; and provided, further, that in the case of any
default of the character specified in SECTION 501(3) with respect to Debt
Securities of such series no such notice to Holders shall be given until at
least 30 days after the default.  For the purpose of this Section,the term 
"default" means any event which is, or after notice or lapse of time or both 
would become, an Event of Default with respect to Debt Securities of such 
series.

                 Notice given pursuant to this SECTION 602 shall be transmitted
by mail:

                 (1)      to all Holders, as the names and addresses of the 
         Holders appear in the Security Register; and

                 (2)      to each Holder of a Debt Security of any series whose
         name and address appear in the information preserved at the time by
         the Trustee in accordance with the Trust Indenture Act.





                                       43

<PAGE>   49
SECTION 603.  CERTAIN RIGHTS OF TRUSTEE.

                 Except as otherwise provided in the Trust Indenture Act:

                 (a)      the Trustee may rely and shall be protected in acting
         or refraining from acting upon any resolution, certificate, statement,
         instrument, opinion, report, notice, request, direction, consent,
         order, bond, debenture, note or other paper or document believed by it
         to be genuine and to have been signed or presented by the proper party
         or parties;

                 (b)      any request or direction of the Company mentioned
         herein shall be sufficiently evidenced by a Company Request or Company
         Order and any resolution of the Board of Directors shall be
         sufficiently evidenced by a Board Resolution;

                 (c)      whenever in the administration of this Indenture the
         Trustee shall deem it desirable that a matter be proved or established
         prior to taking, suffering or omitting any action hereunder, the
         Trustee (unless other evidence be herein specifically prescribed) may,
         in the absence of bad faith on its part, rely upon an Officers'
         Certificate;

                 (d)      the Trustee may consult with counsel and the advice
         of such counsel or any opinion of counsel shall be full and complete
         authorization and protection in respect of any action taken, suffered
         or omitted by it hereunder in good faith and in reliance thereon;

                 (e)      the Trustee shall be under no obligation to exercise
         any of the rights or powers vested in it by this Indenture at the
         request or direction of any of the Holders of Debt Securities of any
         series pursuant to this Indenture, unless such Holders shall have
         offered to the Trustee reasonable security or indemnity against the
         costs, expenses and liabilities that might be incurred by it in
         compliance with such request or direction;

                 (f)      the Trustee shall not be bound to make any
         investigation into the facts or matters stated in any resolution,
         certificate, statement, instrument, opinion, report, notice, request,
         direction, consent, order, bond, debenture, note, other evidence of
         indebtedness or other paper or document (including any mathematical
         calculation contained in any of the foregoing), but the Trustee, in 
         its discretion, may make such further inquiry or investigation into 
         such facts or matters as it may see fit, and, if the Trustee shall
         determine to make such further inquiry or investigation, it shall be
         entitled to examine the books, records and premises of the Company,
         personally or by agent or attorney;

                 (g)      the Trustee may execute any of the trusts or powers
         hereunder or perform any duties hereunder either directly or by or
         through agents or attorneys and the Trustee shall not be responsible
         for any misconduct or negligence on the part of any agent, including
         any agent or attorney appointed with due care by it hereunder; and





                                       44

<PAGE>   50
                 (h)      the Trustee shall not be required to take notice or
         be deemed to have notice of any default hereunder (except failure by
         the Company to pay principal of or interest on any series of
         Securities so long as the Trustee is also acting as Paying Agent for
         such series of Securities) unless the Trustee shall be specifically
         notified in writing of such default by the Company or by the Holders
         of at least a 10% in aggregate principal amount of all Securities then
         outstanding, and all such notices or other instruments required by
         this Indenture to be delivered to the Trustee must, in order to be
         effective, be delivered at the principal Corporate Trust Office of the
         Trustee, and in the absence of such notice the Trustee may
         conclusively assume there is no default except as aforesaid;

                 (i)      the Trustee shall not be liable for any action
         taken, suffered or omitted by it in good faith and reasonably 
         believed by it to be authorized or within the discretion or rights or 
         powers conferred upon it by this Indenture; and 

                 (j)      The permissive right of the Trustee to do things
         enumerated in this Indenture shall not be construed as a duty.

SECTION 604.  NOT RESPONSIBLE FOR RECITALS OR ISSUANCE OF DEBT SECURITIES.

                 The recitals contained herein and in the Debt Securities,
except the Trustee's certificates of authentication, shall be taken as the
statements of the Company, and the Trustee assumes no responsibility for their
correctness.  The Trustee makes no representations as to the  validity or
sufficiency of this Indenture or of the Debt Securities of any series. The 
Trustee shall not be accountable for the use or application by the Company  of 
any Debt Securities or the proceeds thereof.

SECTION 605.  MAY HOLD DEBT SECURITIES.

                 The Trustee, any Paying Agent, the Security Registrar or any
other agent of the Company, in its individual or any other capacity, may become
the owner or pledgee of Debt Securities, and, subject to any incorporated
provisions, may otherwise deal with the Company with the same rights it would
have if it were not the Trustee, Paying Agent, Security Registrar or such other
agent.

SECTION 606.  MONEY HELD IN TRUST.

                 Money in any Currency held by the Trustee or any Paying Agent
in trust hereunder need not be segregated from other funds except to the extent
required by law.  Neither the Trustee nor any Paying Agent shall be under any
liability for interest on any money received by it hereunder except as
otherwise agreed with the Company.

SECTION 607.  COMPENSATION, INDEMNIFICATION AND REIMBURSEMENT.

                 The Company agrees:

                 (1)       to pay to the Trustee from time to time such
         compensation in Dollars for all services rendered by it hereunder
         as shall be agreed upon in writing prior to the performance of such
         services (which compensation shall not be limited by any provision of 
         law in regard to the compensation of a trustee of an express trust);





                                       45

<PAGE>   51
                 (2)      except as otherwise expressly provided herein, to
         reimburse the Trustee in Dollars upon its request for all reasonable
         expenses, disbursements and advances incurred or made by the Trustee
         in accordance with any provision of this Indenture (including the
         reasonable compensation and the expenses and disbursements of its
         agents and counsel), except any such expense, disbursement or advance
         as may be attributable to its negligence or bad faith; and

                 (3)      to indemnify in Dollars the Trustee for, and to hold
         it harmless against, any loss, liability or expense incurred without
         negligence or bad faith on its part arising out of or in connection
         with the acceptance or administration of this trust or performance of
         its duties hereunder, including the costs and expenses of defending
         itself against any claim or liability in connection with the exercise
         or performance of any of its powers or duties hereunder.

                 As security for the performance of the obligations of the
Company under this Section, the Trustee shall have a claim prior to the Debt
Securities upon all property and funds held or collected by the Trustee as
such, except funds held in trust for the payment of amounts due on the Debt
Securities.

                 If the Trustee incurs expenses or renders services after an
Event of Default specified in Section 501(4) or 501(5) occurs, the expenses and
the compensation for the services are intended to constitute expenses of
administration under any bankruptcy, insolvency, reorganization or other
similar law. The obligations of the Company under this SECTION 607 to
compensate and indemnify the Trustee for expenses, disbursements and advances
shall constitute additional indebtedness under this Indenture and shall survive
the satisfaction and discharge of this Indenture.

SECTION 608.  RESIGNATION AND REMOVAL; APPOINTMENT OF SUCCESSOR.

                 (a)      No resignation or removal of the Trustee and no
appointment of a successor Trustee pursuant to this Article shall become
effective until the acceptance of appointment by the successor Trustee under
SECTION 609.

                 (b)      The Trustee may resign at any time with respect to
the Debt Securities of one or more series by giving written notice thereof to
the Company.  If an instrument of acceptance by a successor Trustee shall not
have been delivered to the Trustee within 30 days after the giving of such
notice of resignation, the resigning Trustee may petition any court of
competent jurisdiction for the appointment of a successor Trustee with respect
to the Debt Securities of such series.

                 (c)       The Trustee may be removed at any time with respect
to the Debt Securities of any series and a successor Trustee appointed by Act
of the Holders of a majority in principal amount of the Outstanding Debt
Securities of such series, delivered to the Trustee and to the Company.

                 (d)       If at any time:





                                       46

<PAGE>   52
                 (1)      the Trustee shall fail to comply with Section 310(b)
         of the Trust Indenture Act with respect to the Debt Securities of any
         series after written request therefor by the Company or by any Holder
         who has been a bona fide Holder of a Debt Security of such series for
         at least six months; or

                 (2)      the Trustee shall cease to be eligible under Section
         310(a) of the Trust Indenture Act with respect to the Debt Securities
         of any series and shall fail to resign after written request therefor
         by the Company or by any such Holder; or

                 (3)      the Trustee shall become incapable of acting or shall
         be adjudged a bankrupt or insolvent or a receiver of the Trustee or of
         its property shall be appointed or any public officer shall take
         charge or control of the Trustee or of its property or affairs for the
         purpose of rehabilitation, conservation or liquidation;

then, in any such case, (i) the Company by a Board Resolution may remove the
Trustee with respect to all Debt Securities, or (ii) subject to SECTION 514,
any Holder who has been a bona fide Holder of a Debt Security of any series for
at least six months may, on behalf of himself and all others similarly
situated, petition any court of competent jurisdiction for the removal of the
Trustee and the appointment of a successor Trustee for the Debt Securities of
such series;

                 (e)      If the Trustee shall resign, be removed or become
incapable of acting, or if a vacancy shall occur in the office of Trustee for
any cause, with respect to the Debt Securities of one or more series, the
Company, by a Board Resolution, shall promptly appoint a successor Trustee or
Trustees with respect to the Debt Securities of that or those series (it being
understood that any such successor Trustee may be appointed with respect to the
Debt Securities of one or more or all of such series and that at any time there
shall be only one Trustee with respect to the Debt Securities of any particular
series) and shall comply with the applicable requirements of SECTION 609.  If,
within one year after such resignation, removal or incapability, or the
occurrence of such vacancy, a successor Trustee with respect to the Debt
Securities of any series shall be appointed by Act of the Holders of a majority
in principal amount of the Outstanding Debt Securities of such series delivered
to the Company and the retiring Trustee, the successor Trustee so appointed
shall, forthwith upon its acceptance of such appointment, become the successor
Trustee with respect to the Debt Securities of such series and to that extent
supersede the successor Trustee appointed by the Company.  If no successor
Trustee with respect to the Debt Securities of any series shall have been so
appointed by the Company or the Holders of such series and accepted appointment
in the manner hereinafter provided, any Holder who has been a bona fide Holder
of a Debt Security of such series for at least six months may, subject to
SECTION 514, on behalf of himself and all others similarly situated, petition
any court of competent jurisdiction for the appointment of a successor Trustee
with respect to the Debt Securities of such series.

                 (f)       The Company shall give notice of each resignation
and each removal of the Trustee with respect to the Debt Securities of any
series and each appointment of a successor Trustee with respect to the Debt
Securities of any series in the manner and to the extent provided in SECTION
105 to the Holders of Debt Securities of such series.  Each notice shall
include the





                                       47

<PAGE>   53
name of the successor Trustee with respect to the Debt Securities of such
series and the address of its Corporate Trust Office.

                 (g)      If the Trustee has or shall acquire any conflicting
interest within the meaning of the Trust Indenture Act with respect to the Debt
Securities of any series, it shall either eliminate such conflicting interest
or resign with respect to the Debt Securities of that series in the manner
provided by, and subject to the provisions of, the Trust Indenture Act and this
Indenture, and the Company shall take prompt action to have a successor Trustee
with respect to the Debt Securities of that series appointed in the manner
provided herein.

                 (h)      There shall at all times be a Trustee hereunder with
respect to the Debt Securities of each series, which shall be a Person that is
eligible pursuant to the Trust Indenture Act to act as such, having a combined
capital and surplus of at least $50,000,000, subject to supervision or
examination by Federal or State authority and having its Corporate Trust Office
in Chicago, Illinois or New York, New York.  If such corporation publishes
reports of condition at least annually, pursuant to law or the requirements of
said supervising or examining authority, then for the purposes of this Section,
the combined capital and surplus of such corporation shall be deemed to be its
combined capital and surplus as set forth in its most recent report of
condition so published.  If at any time the Trustee shall cease to be eligible
in accordance with the provisions of this Section, it shall resign immediately
in the manner and with the effect hereinafter specified in this Article.

SECTION 609.  ACCEPTANCE OF APPOINTMENT BY SUCCESSOR.

                 (a)      In the case of an appointment hereunder of a
successor Trustee with respect to all Debt Securities, each such successor
Trustee so appointed shall execute, acknowledge and deliver to the Company and
to the retiring Trustee an instrument accepting such appointment, and thereupon
the resignation or removal of the retiring Trustee shall become effective and
such successor Trustee, without any further act, deed or conveyance, shall
become vested with all the rights, powers, trusts and duties of the retiring
Trustee; but, on request of the Company or the successor Trustee, such retiring
Trustee shall, upon payment of its charges, execute and deliver an instrument
transferring to such successor Trustee all the rights, powers and trusts of the
retiring Trustee, and shall duly assign, transfer and deliver to such successor
Trustee all property and money held by such retiring Trustee hereunder, subject
nevertheless to its claim, if any, provided for in SECTION 607.

                 (b)       In case of the appointment hereunder of a successor
Trustee with respect to the Debt Securities of one or more (but not all)
series, the Company, the retiring Trustee and each successor Trustee with
respect to the Debt Securities of one or more series shall execute and deliver
an indenture supplemental hereto wherein each successor Trustee shall accept
such appointment and which (1) shall contain such provisions as shall be
necessary or desirable to transfer and confirm to, and to vest in, each
successor Trustee all the rights, powers, trusts and duties of the retiring
Trustee with respect to the Debt Securities of that or those series to which
the appointment of such successor Trustee relates, (2) if the retiring Trustee
is not retiring with respect to all Debt Securities, shall contain such
provisions as shall be deemed necessary or





                                       48

<PAGE>   54
desirable to confirm that all the rights, powers, trusts and duties of the
retiring Trustee with respect to the Debt Securities of that or those series as
to which the retiring Trustee is not retiring shall continue to be vested in
the retiring Trustee, and (3) shall add to or change any of the provisions of
this Indenture as shall be necessary to provide for or facilitate the
administration of the trusts hereunder by more than one Trustee, it being
understood that nothing herein or in any such supplemental indenture shall
constitute such Trustees co-trustees of the same trust and that each such
Trustee shall be trustee of a trust or trusts hereunder separate and apart from
any other trust or trusts hereunder administered by any other such Trustee; and
upon the execution and delivery of any such supplemental indenture the
resignation or removal of the retiring Trustee shall become effective to the
extent provided therein and each such successor Trustee, without any further
act, deed or conveyance, shall become vested with all the rights, powers,
trusts and duties of the retiring Trustee with respect to the Debt Securities
of that or those series to which the appointment of such successor Trustee
relates; but, on request of the Company or any successor Trustee, such retiring
Trustee shall duly assign, transfer and deliver to such successor Trustee all
property and money held by such retiring Trustee hereunder with respect to the
Debt Securities of that or those series to which the appointment of such
successor Trustee relates.

                 (c)      Upon request of any such successor Trustee, the
Company shall execute any and all instruments for more fully and certainly
vesting in and confirming to such successor Trustee all such rights, powers and
trusts referred to in paragraph (a) or (b) of this Section, as the case may be.

                 (d)       No successor Trustee shall accept its appointment
unless at the time of such acceptance such successor Trustee shall be qualified
and eligible under this Article.

SECTION 610.  MERGER, CONVERSION, CONSOLIDATION OR SUCCESSION TO BUSINESS.

                 Any corporation into which the Trustee may be merged or
converted or with which it may be consolidated, or any corporation resulting
from any merger, conversion or consolidation to which the Trustee shall be a
party, or any corporation succeeding to all or substantially all of the
corporate trust business of the Trustee, shall be the successor of the Trustee
hereunder, provided that such corporation shall be otherwise qualified and
eligible under this Article, without the execution or filing of any paper or
any further act on the part of any of the parties hereto.  In case any Debt
Securities shall have been authenticated, but not delivered, by the Trustee
then in office, any successor by merger, conversion or consolidation to such
authenticating Trustee may adopt such authentication and deliver the Debt
Securities so authenticated with the same effect as if such successor Trustee
had itself authenticated such Debt Securities.  In case any Debt Securities
shall not have been authenticated by such predecessor Trustee, any such
successor Trustee may authenticate and deliver such Debt Securities, in either
its own name or that of its predecessor Trustee, with the full force and effect
which this Indenture provides for the certificate of authentication of the
Trustee.





                                       49

<PAGE>   55
SECTION 611.  APPOINTMENT OF AUTHENTICATING AGENT.

                 As long as any Debt Securities of a series remain Outstanding,
upon a Company Request, there shall be an authenticating agent (the
"Authenticating Agent") appointed, for such period as the Company shall elect,
by the Trustee for such series of Debt Securities to act as its agent on its
behalf and subject to its direction in connection with the authentication and
delivery of each series of Debt Securities for which it is serving as Trustee.
Debt Securities of each such series authenticated by such Authenticating Agent
shall be entitled to the benefits of this Indenture and shall be valid and
obligatory for all purposes as if authenticated by such Trustee.  Wherever
reference is made in this Indenture to the authentication and delivery of Debt
Securities of any series by the Trustee for such series or to the Trustee's
Certificate of Authentication, such reference shall be deemed to include
authentication and delivery on behalf of the Trustee for such series by an
Authenticating Agent for such series and a Certificate of Authentication
executed on behalf of such Trustee by such Authenticating Agent.  Such 
Authenticating Agent shall at all times be a corporation organized and doing 
business under the laws of the United States of America or of any State, 
authorized under such laws to exercise corporate trust powers, having a 
combined capital and surplus of at least $25,000,000 and subject to 
supervision or examination by federal or state authority.  If such 
Authenticating Agent publishes reports of condition at least annually, pursuant 
to law or to the requirements of said supervising or examining authority, then 
for purposes of this Section, the combined capital and surplus of such 
Authenticating Agent shall be deemed to be its combined capital and surplus as 
set forth in its most recent report of condition so published.  If at any time 
an Authenticating Agent shall cease to be eligible in accordance with the 
provisions of this Section, such Authenticating Agent shall resign immediately 
in the manner and with the effect specified in this Section.

                 Any corporation into which any Authenticating Agent may be
merged or converted, or with which it may be consolidated, or any corporation
resulting from any merger, conversion or consolidation to which any
Authenticating Agent shall be a party, or any corporation succeeding to the
corporate agency business of any Authenticating Agent, shall continue to be the
Authenticating Agent (provided that such corporation shall be otherwise
eligible under this SECTION 611 to serve as Authenticating Agent) with respect
to all series of Debt Securities for which it served as Authenticating Agent
without the execution or filing of any paper or any further act on the part of
the Trustee for such series or such Authenticating Agent.  Any Authenticating
Agent may at any time, and if it shall cease to be eligible,  shall resign by
giving written notice of resignation to the applicable Trustee and to the
Company.

                 Upon receiving such a notice of resignation or upon such a
termination, or in case at any time any Authenticating Agent shall cease to be
eligible in accordance with the provisions of this SECTION 611 with respect to
one or more of all series of Debt Securities, the Trustee for such series shall
upon Company Request appoint a successor Authenticating Agent, and the Company
shall provide notice of such appointment to all Holders of Debt Securities of
such series in the manner and to the extent provided in SECTION 105.  Any
successor Authenticating Agent upon acceptance of its appointment hereunder
shall become vested with all rights, powers,





                                       50

<PAGE>   56
duties and responsibilities of its predecessor hereunder, with like effect as
if originally named as Authenticating Agent herein.  The Trustee for the Debt
Securities of such series agrees to pay to the Authenticating Agent for such
series from time to time reasonable compensation for its services, and the
Trustee shall be entitled to be reimbursed for such payment, subject to the
provisions of SECTION 607.  The Authenticating Agent for the Debt Securities of
any series shall have no responsibility or liability for any action taken by it
as such at the direction of the Trustee for such series.

                 If an appointment with respect to one or more series is made
pursuant to this Section, the Debt Securities of such series may have endorsed
thereon, an alternative certificate of authentication in the following form:

                 This is one of the series of Debt Securities issued under the
within mentioned Indenture.

                                        TEXAS COMMERCE BANK NATIONAL
                                        ASSOCIATION, as Trustee


                                        By ____________________________________
                                                  As Authenticating Agent


                                        By ____________________________________
                                                   Authorized Signatory


SECTION 612.  PREFERENTIAL COLLECTION OF CLAIMS AGAINST COMPANY.

         If and when the Trustee becomes a creditor of the Company (or any
other obligor upon the Debt Securities), the Trustee shall be subject to the
provisions of the Trust Indenture Act regarding the collection of claims
against the Company (or any such other obligor).  A Trustee that has resigned
or been removed is subject to such provisions of the Trust Indenture Act to the
extent provided therein.


                                 ARTICLE SEVEN

                             CONCERNING THE HOLDERS

SECTION 701.  ACTS OF HOLDERS; RECORD DATES.

                 (a)     Any request, demand, authorization, direction, notice,
consent, waiver or other action provided by this Indenture to be given or taken
by Holders may be embodied in and





                                       51

<PAGE>   57
evidenced by one or more instruments of substantially similar tenor signed by
such Holders in person or by an agent or proxy duly appointed in writing; and,
except as herein otherwise expressly provided, such action shall become
effective when such instrument or instruments are delivered to the Trustee,
and, where it is hereby expressly required, to the Company.  Such instrument or
instruments (and the action embodied therein and evidenced thereby) are herein
sometimes referred to as the "Act" of the Holders signing such instrument or
instruments.  Whenever in this Indenture it is provided that the Holders of a
specified percentage in aggregate principal amount of the Outstanding Debt
Securities of any series may take any Act, the fact that the Holders of such
specified percentage have joined therein may be evidenced (a) by the instrument
or instruments executed by Holders in person or by agent or proxy appointed in
writing, or (b) by the record of Holders voting in favor thereof at any meeting
of such Holders duly called and held in accordance with the provisions of
ARTICLE EIGHT, or (c) by a combination of such instrument or instruments and
any such record of such a meeting of Holders.

                 (b)    For purposes of any provision of the Indenture where
the Holders of Outstanding Debt Securities may perform an Act that requires
that a specified percentage of the Outstanding Debt Securities of all series
perform such Act and for purposes of any decision or determination by the
Trustee and the Paying Agent of amounts due and unpaid for the principal of 
(and premium, if any) and interest on the Debt Securities of all series in 
respect of which moneys are to be disbursed ratably, the principal of (and
premium, if any) and interest on the Outstanding Debt Securities denominated in
Foreign Currency will be the amount in Dollars based upon the Market Exchange
Rate for Debt Securities of such series, as of the date for determining whether
the Holders entitled to perform such Act have performed it, or as of the date
of such decision or determination by the Trustee, as the case may be. 
        
                 (c)    Except as provided in the next paragraph of this
subsection (c), the Company may set any day as the record date for the purpose
of determining the Holders entitled to perform any act, or to vote on any 
action, authorized or permitted to be given or taken by Holders. With regard to
any record date set pursuant to this subsection (c), the Holders of Outstanding
Debt Securities of the relevant series on such record date (or their duly
appointed agents), and only such Persons, shall be entitled to give or take the
relevant action, whether or not such Holders remain Holders after such record
date. Whenever in this Indenture it is provided that the Holders of a specified
percentage in aggregate principal amount of the Outstanding Debt Securities of
any series (or their duly appointed agents) may take any Act and for which a
record date is set pursuant to this subsection (c), the Company may, at its
option, set an expiration date after which no such Act purported to be given or
taken by any Holder shall be effective hereunder unless given or taken on or
prior to such expiration date by Holders of the requisite principal amount of
Outstanding Debt Securities of such series on such record date (or their duly
appointed agents), which expiration date shall be at least 30 days after notice
thereof is given in writing to the Trustee and the Holders.  On or prior to any 
expiration date set pursuant to this subsection (c), the Company may extend 
such date to any later date by providing written notice of such extension to
the Trustee and the Holders.
        
                 Notwithstanding the foregoing, upon receipt by the Trustee,
with respect to Securities of any series, of (i) any notice of the occurrence
of Event of Default pursuant to Section 501(3), (ii) any declaration of 
acceleration, or any rescission and annulment of any such declaration pursuant
to Section 502, or (iii) any direction given pursuant to Section 512 (any of
the foregoing being referred to herein as a "Direction"), a record date shall
automatically and without any other action by any Person be set for the purpose
of determining the Holders of the Outstanding Debt Securities of such series
entitled to join in such Direction, which record date shall be the close of
business on the day the Trustee receives such Direction. The Holders of the
Outstanding Debt Securities of such series on such record date (or their duly
appointed agents), and only such Persons, shall be entitled to join in such
Direction, whether or not such Holders remain Holders after such record date;
provided that, unless such Direction shall have become effective by virtue of
Holders of the specified percentage in aggregate principal amount of the
Outstanding Debt Securities of such series on such record date (or their duly
appointed agents) having joined therein on or prior to the 90th day after such
record date, such Direction shall automatically and without any action by any
Person be cancelled and be of no further effect. Nothing in this paragraph
shall prevent a Holder (or a duly appointed agent thereof) from giving, before
or after the expiration of such 90-day period, a Direction contrary to or
different from, or, after the expiration of such period, identical to, a
Direction that has been cancelled pursuant to the proviso to the preceding
sentence, in which event a new record date in respect thereof shall be set
pursuant to this subsection (c).
        
SECTION 702. PROOF OF OWNERSHIP; PROOF OF EXECUTION OF INSTRUMENTS BY HOLDERS.

                 The ownership of Debt Securities of any series shall be proved
by the Security Register for such series or by a certificate of the Security
Registrar for such series.

                 Subject to the provisions of SECTION 603 and 805, proof of the
execution of a writing appointing an agent or proxy and of the execution of any
instrument by a Holder or his agent or proxy shall be sufficient and conclusive
in favor of the Trustee and the Company if made in the following manner:

                 The fact and date of the execution by any such person of any
instrument may be proved by the certificate of any notary public or other
officer authorized to take acknowledgement of deeds, that the person executing
such instrument acknowledged to him the execution thereof, or by an affidavit
of a witness to such execution sworn to before any such notary or other such
officer.  Where such execution is by an officer of a corporation or association
or a member of a partnership on behalf of such corporation, association or
partnership, as the case may be, or by any other person acting in a
representative capacity, such certificate or affidavit shall also constitute
sufficient proof of his authority.

                 The record of any Holders' meeting shall be proved in the 
manner provided in SECTION 806.

                 The Trustee may in any instance require further proof with
respect to any of the matters referred to in this Section so long as the
request is a reasonable one.

SECTION 703.  PERSONS DEEMED OWNERS.

                 The Company, the Trustee and any agent of the Company or the
Trustee may treat the Person in whose name any Debt Security is registered as
the owner of such Debt Security for the purpose of receiving payment of the
principal of (and premium, if any) and (subject to SECTION 307) interest, if
any, on such Debt Security and for all other purposes





                                       52


<PAGE>   58
whatsoever, whether or not such Debt Security be overdue, and neither the
Company, the Trustee nor any agent of the Company or the Trustee shall be
affected by notice to the contrary.  All payments made to any Holder, or upon
his order, shall be valid, and, to the extent of the sum or sums paid,
effectual to satisfy and discharge the liability for moneys payable upon such
Debt Security.

SECTION 704.  REVOCATION OF CONSENTS; FUTURE HOLDERS BOUND.

                 At any time prior to (but not after) the evidencing to the
Trustee, as provided in SECTION 701, of the taking of any Act by the Holders of
the percentage in aggregate principal amount of the Outstanding Debt Securities
specified in this Indenture in connection with such Act, any Holder of a Debt
Security the number, letter or other distinguishing symbol of which is shown by
the evidence to be included in the Debt Securities the Holders of which have
consented to such Act may, by filing written notice with the Trustee at the
Corporate Trust Office and upon proof of ownership as provided in SECTION 702,
revoke such Act so far as it concerns such Debt Security.  Except as aforesaid,
any such Act taken by the Holder of any Debt Security shall be conclusive and
binding upon such Holder and upon all future Holders of such Debt Security and
of any Debt Securities issued on transfer or in lieu thereof or in exchange or
substitution therefor, irrespective of whether or not any notation in regard
thereto is made upon such Debt Security or such other Debt Securities.


                                 ARTICLE EIGHT

                               HOLDERS' MEETINGS

SECTION 801.  PURPOSES OF MEETINGS.

                 A meeting of Holders of any or all series may be called at any
time and from time to time pursuant to the provisions of this ARTICLE EIGHT for
any of the following purposes:

                 (1)      to give any notice to the Company or to the Trustee
         for any series of Debt Securities or to give any directions to the
         Trustee for such series, or to consent to the waiving of any default
         hereunder and its consequences, or to take any other action authorized
         to be taken by Holders pursuant to any of the provisions of ARTICLE
         FIVE;

                 (2)      to remove the Trustee for such series and appoint a
         successor Trustee pursuant to the provisions of ARTICLE SIX;

                 (3)      to consent to the execution of an indenture or
         indentures supplemental hereto pursuant to the provisions of SECTION
         1002; or

                 (4)      to take any other action authorized to be taken by or
         on behalf of the Holders of any specified aggregate principal amount
         of the Outstanding Debt Securities





                                       53

<PAGE>   59
         of any one or more or all series, as the case may be, under any other
         provision of this Indenture or under applicable law.

SECTION 802.  CALL OF MEETINGS BY TRUSTEE.

                 The Trustee for any series may at any time call a meeting of
Holders of such series to take any action specified in SECTION 801, to be held
at such time or times and at such place or places as the Trustee for such
series shall determine.  Notice of every meeting of the Holders of any series,
setting forth the time and the place of such meeting and in general terms the
action proposed to be taken at such meeting, shall be given to Holders of such
series in the manner and to the extent provided in SECTION 105.  Such notice
shall be given not less than 20 days nor more than 90 days prior to the date
fixed for the meeting.

SECTION 803.  CALL OF MEETINGS BY COMPANY OR HOLDERS.

                 In case at any time the Company, pursuant to a Board
Resolution, or the Holders of at least 10% in aggregate principal amount of the
Outstanding Debt Securities of a series or of all series, as the case may be,
shall have requested the Trustee for such series to call a meeting of Holders
of any or all such series by written request setting forth in reasonable detail
the action proposed to be taken at the meeting, and the Trustee shall not have
given the notice of such meeting within 20 days after the receipt of such
request, then the Company or such Holders may determine the time or times and
the place or places for such meetings and may call such meetings to take any
action authorized in SECTION 801, by giving notice thereof as provided in
SECTION 802.

SECTION 804.  QUALIFICATIONS FOR VOTING.

                 To be entitled to vote at any meeting of Holders a Person
shall be (a) a Holder of a Debt Security of the series with respect to which
such meeting is being held or (b) a Person appointed by an instrument in
writing as agent or proxy by such Holder.  The only Persons who shall be
entitled to be present or to speak at any meeting of Holders shall be the
Persons entitled to vote at such meeting and their counsel and any
representatives of the Trustee for the series with respect to which such
meeting is being held and its counsel and any representatives of the Company
and its counsel.

SECTION 805.  REGULATIONS.

                 Notwithstanding any other provisions of this Indenture, the
Trustee for any series may make such reasonable regulations as it may deem
advisable for any meeting of Holders of such series, in regard to proof of the
holding of Debt Securities of such series and of the appointment of proxies,
and in regard to the appointment and duties of inspectors of votes, the
submission and examination of proxies, certificates and other evidence of the
right to vote, and such other matters concerning the conduct of the meeting as
it shall deem appropriate.





                                       54

<PAGE>   60
                 The Trustee shall, by an instrument in writing, appoint a
temporary chairman of the meeting, unless the meeting shall have been called by
the Company or by Holders of such series as provided in SECTION 803, in which
case the Company or the Holders calling the meeting, as the case may be, shall
in like manner appoint a temporary chairman.  A permanent chairman and a
permanent secretary of the meeting shall be elected by a majority vote of the
meeting.

                 Subject to the provisos in the definition of "Outstanding," at
any meeting each Holder of a Debt Security of the series with respect to which
such meeting is being held or proxy therefor shall be entitled to one vote for
each $1,000 principal amount (or such other amount as shall be specified as
contemplated by SECTION 301) of Debt Securities of such series held or
represented by him; provided, however, that no vote shall be cast or counted at
any meeting in respect of any Debt Security challenged as not Outstanding and
ruled by the chairman of the meeting to be not Outstanding.  The chairman of
the meeting shall have no right to vote other than by virtue of Outstanding
Debt Securities of such series held by him or instruments in writing duly
designating him as the person to vote on behalf of Holders of Debt Securities
of such series.  Any meeting of Holders with respect to which a meeting was
duly called pursuant to the provisions of SECTION 802 or 803 may be adjourned
from time to time by a majority of such Holders present and the meeting may be
held as so adjourned without further notice.

SECTION 806.  VOTING.

                 The vote upon any resolution submitted to any meeting of
Holders with respect to which such meeting is being held shall be by written
ballots on which shall be subscribed the signatures of such Holders or of their
representatives by proxy and the serial number or numbers of the Debt
Securities held or represented by them.  The permanent chairman of the meeting
shall appoint two inspectors of votes who shall count all votes cast at the
meeting for or against any resolution and who shall make and file with the
secretary of the meeting their verified written reports in duplicate of all
votes cast at the meeting.  A record in duplicate of the proceedings of each
meeting of Holders shall be prepared by the secretary of the meeting and there
shall be attached to said record the original reports of the inspectors of
votes on any vote by ballot taken thereat and affidavits by one or more persons
having knowledge of the facts setting forth a copy of the notice of the meeting
and showing that said notice was transmitted as provided in SECTION 802.  The
record shall show the serial numbers of the Debt Securities voting in favor of
or against any resolution.  The record shall be signed and verified by the
affidavits of the permanent chairman and secretary of the meeting and one of
the duplicates shall be delivered to the Company and the other to the Trustee
to be preserved by the Trustee.

                 Any record so signed and verified shall be conclusive evidence
of the matters therein stated.

SECTION 807.  NO DELAY OF RIGHTS BY MEETING.

                 Nothing contained in this ARTICLE EIGHT shall be deemed or
construed to authorize or permit, by reason of any call of a meeting of Holders
or any rights expressly or impliedly





                                       55

<PAGE>   61
conferred hereunder to make such call, any hindrance or delay in the exercise
of any right or rights conferred upon or reserved to the Trustee or to any
Holder under any of the provisions of this Indenture or of the Debt Securities
of any series.

SECTION 808.  QUORUM: ACTION.

                 The Persons entitled to vote a majority in aggregate principal
amount of the Outstanding Debt Securities of a series shall constitute a quorum
for a meeting of Holders of Debt Securities of such series, provided, however,
that if any action is to be taken at such meeting with respect to a consent or
waiver which this Indenture expressly provides may be given by the Holders of a
specified percentage, which is greater than a majority in aggregate principal
amount of the Outstanding Debt Securities of a series, the Persons entitled to
vote such specified percentage in aggregate principal amount of the Outstanding
Debt Securities of such series, shall constitute a quorum.

                                  ARTICLE NINE

              CONSOLIDATION, MERGER, CONVEYANCE, TRANSFER OR LEASE

SECTION 901.  COMPANY MAY CONSOLIDATE, ETC., ONLY ON CERTAIN TERMS.

                 The Company shall not consolidate with or merge into any other
Person or convey, transfer or lease its properties and assets substantially as
an entirety to any Person, unless:

                 (1)      the Person formed by such consolidation or into which
         the Company is merged or the Person which acquires by conveyance or
         transfer, or which leases, the properties and assets of the Company
         substantially as an entirety (the "successor corporation") shall be a
         corporation organized and existing under the laws of the United States
         of America or any state or the District of Columbia and shall
         expressly assume, by an indenture supplemental hereto, executed and
         delivered to the Trustee, in form reasonably satisfactory to the
         Trustee, the due and punctual payment of the principal of (and
         premium, if any) and interest on all the Debt Securities and the
         performance of every covenant of this Indenture on the part of the
         Company to be performed or observed;

                 (2)      immediately after giving effect to such transaction,
         no Event of Default, and no event which, after notice or lapse of
         time, or both would become an Event of Default, shall have happened
         and be continuing; and

                 (3)      if, as a result of any such consolidation or merger
         or such conveyance, transfer or lease, properties or assets of the
         Company would become subject to a mortgage, pledge, lien, security
         interest or other encumbrance that would not be permitted by this
         Indenture, the Company or such successor Person, as the case may be,





                                       56

<PAGE>   62
         shall take such steps as shall be necessary effectively to secure all
         Debt Securities equally and ratably with (or prior to) all
         indebtedness secured thereby; and

                 (4)      the Company has delivered to the Trustee an Officers'
         Certificate and an Opinion of Counsel each stating that such
         consolidation, merger, conveyance, transfer or lease and such
         supplemental indenture comply with this ARTICLE NINE, that all
         conditions precedent herein provided for relating to such transaction
         have been complied with and that the execution and delivery of such
         supplemental indenture has been duly authorized by all necessary
         corporate action of the successor Person, such supplemental indenture
         has been duly executed and delivered by the successor Person and,
         assuming due authorization, execution and delivery by the Trustee, is
         a valid and binding obligation enforceable against the successor
         Person in accordance with its terms, subject to applicable bankruptcy,
         insolvency and similar laws affecting creditors' rights generally and
         subject, as to enforceability, to general principles of equity
         (regardless of whether enforcement is sought in a proceeding in equity
         or at law).

SECTION 902.  SUCCESSOR CORPORATION SUBSTITUTED.

                 Upon any consolidation with or merger into any other Person,
or any conveyance, transfer or lease of the properties and assets of the
Company substantially as an entirety in accordance with SECTION 901, the
successor Person formed by such consolidation or into which the Company is
merged or to which such conveyance, transfer or lease is made shall succeed to,
and be substituted for, and may exercise every right and power of, the Company
under this Indenture with the same effect as if such successor corporation had
been named as the Company herein, and thereafter the predecessor corporation
shall be relieved of all obligations and covenants under this Indenture and the
Debt Securities.


                                  ARTICLE TEN

                            SUPPLEMENTAL INDENTURES

SECTION 1001.  SUPPLEMENTAL INDENTURES WITHOUT CONSENT OF HOLDERS.

                 Without the consent of any Holders, the Company, when
authorized by a Board Resolution, and the Trustee, at any time and from time to
time, may enter into one or more indentures supplemental hereto, in form
satisfactory to the Trustee, for any of the following purposes:

                 (1)       to evidence the succession of another corporation to
         the Company and the assumption by such successor of the covenants of
         the Company herein and in the Debt Securities contained; or

                 (2)       to add to the covenants of the Company, for the
         benefit of the Holders of all or any series of Debt Securities
         appertaining thereto (and if such covenants are to be





                                       57

<PAGE>   63
         for the benefit of less than all series, stating that such covenants
         are expressly being included solely for the benefit of such series),
         or to surrender any right or power herein conferred upon the Company;
         or

                 (3)      to add any additional Events of Default (and if such
         Events of Default are to be applicable to less than all series,
         specifying the series to which such Events of Default are applicable
         and stating that such Events of Default are expressly being included
         solely to be applicable to such series); or

                 (4)      to add to, change or eliminate any of the provisions
         of this Indenture, provided that any such addition, change or
         elimination shall become effective only when there is no Outstanding
         Debt Security of any series created prior to the execution of such
         supplemental indenture that is entitled to the benefit of such
         provision and as to which such supplemental indenture would apply; or

                 (5)      to secure the Debt Securities; or

                 (6)      to supplement any of the provisions of this Indenture
         to such extent as shall be necessary to permit or facilitate the
         defeasance and discharge of any series of Debt Securities pursuant to
         ARTICLE FOUR OR ARTICLE THIRTEEN provided that any such action shall
         not adversely affect the interests of the Holders of Debt Securities
         of such series or any other series of Debt Securities in any material
         respect; or

                 (7)      to establish the form or terms of Debt Securities of
         any series as permitted by SECTIONS 201 and 301; or

                 (8)      to evidence and provide for the acceptance of
         appointment hereunder by a successor Trustee with respect to one or
         more series of Debt Securities and to add to or change any of the
         provisions of this Indenture as shall be necessary to provide for or
         facilitate the administration of the trusts hereunder by more than one
         Trustee, pursuant to the requirements of SECTION 609; or

                 (9)      to cure any ambiguity, to correct or supplement any
         provision herein which may be defective or inconsistent with any other
         provision herein, or to make any other provisions with respect to
         matters or questions arising under this Indenture which shall not be
         inconsistent with any provision of this Indenture, provided such other
         provisions shall not adversely affect the interests of the Holders of
         Outstanding Debt Securities of any series created prior to the
         execution of such supplemental indenture in any material respect; or

                 (10)     to change any place or places where (1) the principal
         of and premium, if any, and interest, if any, on all or any series of
         Debt Securities shall be payable, (2) all or any series of Debt
         Securities may be surrendered for registration or transfer, (3) all or
         any series of Debt Securities may be surrendered for exchange, and (4)
         notices and





                                       58

<PAGE>   64
         demands to or upon the Company in respect of all or any series of Debt
         Securities and this Indenture may be served; or.

                 (11)     to change any provision of this Indenture relating to
         payments in Foreign Currencies or Currency units to facilitate the
         making of such payments; provided that any such action shall not
         adversely affect the interests of the Holders of Debt Securities of
         such series or any other series of Debt Securities in any material
         respect.

SECTION 1002.  SUPPLEMENTAL INDENTURES WITH CONSENT OF HOLDERS.

                 With the consent of the Holders of not less than a majority in
principal amount of the Outstanding Debt Securities of each series affected by
such supplemental indenture voting separately, by Act of said Holders delivered
to the Company and the Trustee, the Company, when authorized by a Board
Resolution, and the Trustee may enter into an indenture or indentures
supplemental hereto for the purpose of adding any provisions to or changing in
any manner or eliminating any of the provisions of this Indenture or of
modifying in any manner the rights of the Holders under this Indenture of such
Debt Securities; provided, however, that no such supplemental indenture shall,
without the consent of the Holder of each outstanding Debt Security of each
such series affected thereby,

                 (1)       change the Stated Maturity of the principal of, or
         installment of interest, if any, on, any Debt Security, or reduce the
         principal amount thereof or the interest thereon or any premium
         payable upon redemption thereof, or change the Currency or Currencies
         in which the principal of (and premium, if any) or interest on such
         Debt Security is denominated or payable, or reduce the amount of the
         principal of a Discount Security that would be due and payable upon a
         declaration of acceleration of the Maturity thereof pursuant to
         SECTION 502, or adversely affect the right of repayment or repurchase,
         if any, at the option of the Holder, or impair the right to institute 
         suit for the enforcement of any payment on or after the Stated 
         Maturity thereof (or, in the case of redemption, on or after the
         Redemption Date); or

                 (2)       reduce the percentage in principal amount of the
         Outstanding Debt Securities of any series, the consent of whose
         Holders is required for any supplemental indenture, or the consent of
         whose Holders is required for any waiver of compliance with certain
         provisions of this Indenture or certain defaults hereunder and their
         consequences provided for in this Indenture; or

                 (3)       modify any of the provisions of this Section,
         SECTION 513 or SECTION 1105, except to increase any such percentage or
         to provide that certain other provisions of this Indenture cannot be
         modified or waived without the consent of the Holder of each
         Outstanding Debt Security affected thereby; provided, however, that
         this clause shall not be deemed to require the consent of any Holder
         with respect to changes in the references to "the Trustee" and
         concomitant changes in this Section and SECTION 1105, or the





                                       59

<PAGE>   65
         deletion of this proviso, in accordance with the requirements of 
         SECTIONS 609 and 1001(7).

                 It shall not be necessary for any Act of Holders under this
Section to approve the particular form of any proposed supplemental indenture,
but it shall be sufficient if such Act shall approve the substance thereof.

                 A supplemental indenture which changes or eliminates any
covenant or other provision of this Indenture with respect to one or more
particular series of Debt Securities or which modifies the rights of the
Holders of Debt Securities of such series with respect to such covenant or
other provision, shall be deemed not to affect the rights under this Indenture
of the Holders of Debt Securities of any other series.

SECTION 1003.  EXECUTION OF SUPPLEMENTAL INDENTURES.

                 In executing, or accepting the additional trusts created by,
any supplemental indenture permitted by this Article or the modifications
thereby of the trusts created by this Indenture, the Trustee shall be entitled
to receive, and (subject to any incorporated provisions) shall be fully
protected in relying upon, an Opinion of Counsel stating that the execution of
such supplemental indenture is authorized or permitted by this Indenture and
that the execution and delivery of such supplemental indenture has been duly
authorized by all necessary corporate action of the Company, such supplemental
indenture has been duly executed and delivered by the Company and, assuming due
authorization, execution and delivery by the Trustee, is a valid and binding
obligation enforceable against the Company in accordance with its terms,
subject to applicable bankruptcy, insolvency and similar laws affecting
creditors' rights generally and subject, as to enforceability, to general
principles of equity (regardless of whether enforcement is sought in a
proceeding in equity or at law).  The Trustee may, but shall not be obligated
to, enter into any such supplemental indenture which adversely affects the
Trustee's own rights, duties or immunities under this Indenture or otherwise in
a material way.

SECTION 1004.  EFFECT OF SUPPLEMENTAL INDENTURES.

                 Upon the execution of any supplemental indenture under this
Article, this Indenture shall be modified in accordance therewith, and such
supplemental indenture shall form a part of this Indenture for all purposes;
and every Holder of Debt Securities theretofore or thereafter authenticated and
delivered hereunder shall be bound thereby.

SECTION 1005.  CONFORMITY WITH TRUST INDENTURE ACT.

                 Every supplemental indenture executed pursuant to this Article
shall conform to the requirements of the Trust Indenture Act as then in effect.





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<PAGE>   66
SECTION 1006.  REFERENCE IN DEBT SECURITIES TO SUPPLEMENTAL INDENTURES.

                 Debt Securities of any series authenticated and delivered
after the execution of any supplemental indenture pursuant to this Article may,
and shall if required by the Company or the Trustee, bear a notation in form
approved by the Trustee as to any matter provided for in such supplemental
indenture.  If the Company shall so determine, new Debt Securities of any
series so modified as to conform, in the opinion of the Trustee and the Board
of Directors, to any such supplemental indenture may be prepared and executed
by the Company and authenticated and delivered by the Trustee in exchange for
Outstanding Debt Securities of such series.

SECTION 1007.  NOTICE OF SUPPLEMENTAL INDENTURE.

                 Promptly after the execution by the Company and the
appropriate Trustee of any supplemental indenture pursuant to SECTION 1002, the
Company shall transmit, in the manner and to the extent provided in SECTION
105, to all Holders of any series of the Debt Securities affected thereby, a
notice setting forth in general terms the substance of such supplemental
indenture.


                                 ARTICLE ELEVEN

                                   COVENANTS

SECTION 1101.  PAYMENT OF PRINCIPAL, PREMIUM AND INTEREST.

                 The Company covenants and agrees for the benefit of each
series of Debt Securities that it will duly and punctually pay the principal of
(and premium, if any) and interest on the Debt Securities in accordance with
the terms of the Debt Securities and this Indenture.

SECTION 1102.  MAINTENANCE OF OFFICE OR AGENCY.

                 The Company will maintain in each Place of Payment for each
series of Debt Securities an office or agency where Debt Securities of that
series may be presented or surrendered for payment, where Debt Securities of
that series may be surrendered for registration of transfer or exchange and
where notices and demands to or upon the Company in respect of the Debt
Securities of that series and this Indenture may be served.  The Company will
give prompt written notice to the Trustee of the location, and any change in
the location, of such office or agency.  If at any time the Company shall fail
to maintain any such required office or agency or shall fail to furnish the
Trustee with the address thereof, such presentations, surrenders, notices and
demands may be made or served at the Corporate Trust Office of the Trustee, and
the Company hereby appoints the Trustee as its agent to receive all
presentations, surrenders, notices and demands.





                                       61

<PAGE>   67
SECTION 1103.  MONEY FOR DEBT SECURITIES; PAYMENTS TO BE HELD IN TRUST.

                 If the Company shall at any time act as its own Paying Agent
with respect to any series of Debt Securities, it will, on or before each due
date of the principal of (and premium, if any) or interest on any of the Debt
Securities of such series, segregate and hold in trust for the benefit of the
Persons entitled thereto a sum sufficient to pay the principal (and premium, if
any) or interest so becoming due until such sums shall be paid to such Persons
or otherwise disposed of as herein provided, and will promptly notify the
Trustee of its action or failure so to act.

                 Whenever the Company shall have one or more Paying Agents with
respect to any series of Debt Securities, it will, by or on each due date of
the principal (and premium, if any) or interest on any Debt Securities of such
series, deposit with any such Paying Agent a sum sufficient to pay the
principal (and premium, if any) or interest so becoming due, such sum to be
held in trust for the benefit of the Persons entitled thereto, and (unless any
such Paying Agent is the Trustee) the Company will promptly notify the Trustee
of its action or failure so to act.

                 The Company will cause each Paying Agent with respect to any
series of Debt Securities other than the Trustee to execute and deliver to the
Trustee an instrument in which such Paying Agent shall agree with the Trustee,
subject to the provisions of this Section, that such Paying Agent will:

                 (1)       hold all sums held by it for the payment of the
         principal of (and premium, if any) or interest on Debt Securities of
         such series in trust for the benefit of the Persons entitled thereto
         until such sums shall be paid to such Persons or otherwise disposed of
         as herein provided;

                 (2)       give the Trustee notice of any default by the
         Company (or any other obligor upon the Debt Securities of such series)
         in the making of any payment of principal (and premium, if any) or
         interest on the Debt Securities of such series; and

                 (3)       at any time during the continuance of any such
         default, upon the written request of the Trustee, forthwith pay to the
         Trustee all sums so held in trust by such Paying Agent.

                 The Company may at any time, for the purpose of obtaining the
satisfaction and discharge of this Indenture or for any other purpose, pay, or
by Company Order direct any Paying Agent to pay, to the Trustee all sums held
in trust by the Company or such Paying Agent, such sums to be held by the
Trustee upon the same trusts as those upon which such sums were held by the
Company or such Paying Agent; and, upon such payment by any Paying Agent to the
Trustee, such Paying Agent shall be released from all further liability with
respect to such money.

                 Any money deposited with the Trustee or any Paying Agent, or
then held by the Company, in trust for the payment of the principal of (and
premium, if any) or interest on any





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<PAGE>   68
Debt Security of any series and remaining unclaimed for two years after such
principal (and premium, if any) or interest has became due and payable shall be
paid to the Company upon Company Request, or (if then held by the Company)
shall be discharged from such trust; and the Holder of such Debt Security shall
thereafter, as an unsecured general creditor, look only to the Company for
payment thereof, and all liability of the Trustee or such Paying Agent with
respect to such trust money, and all liability of the Company as trustee
thereof, shall thereupon cease; provided, however, that the Trustee or such
Paying Agent, before being required to make any such repayment, may at the
expense of the Company cause to be transmitted in the manner and to the extent
provided by SECTION 105, notice that such money remains unclaimed and that,
after a date specified therein, which shall not be less than 30 days from the
date of such notification, any unclaimed balance of such money then remaining
will be repaid to the Company.

SECTION 1104.  CORPORATE EXISTENCE.

                 Subject to ARTICLE NINE, the Company will do or cause to be
done all things necessary to preserve and keep in full force and effect its
corporate existence, rights (charter and statutory) and franchises; provided,
however, that the Company shall not be required to preserve any such right or
franchise if the Company shall determine that the preservation thereof is no
longer desirable in the conduct of the business of the Company.

SECTION 1105. OFFICERS' CERTIFICATE AS TO DEFAULT.

                 The Company will deliver to the Trustee, on or before a date
not more than four months after the end of each fiscal year of the Company
ending after the date hereof, an Officers' Certificate stating whether or not
to the best knowledge of the signers thereof the Company is in default in the
performance and observation of any of the terms, provisions and conditions of
this Indenture, and, if the Company shall be in default, specifying all such
defaults and the nature thereof of which they may have knowledge.












                                       63

<PAGE>   69
                                 ARTICLE TWELVE

                         REDEMPTION OF DEBT SECURITIES

SECTION 1201.  APPLICABILITY OF ARTICLE.

                 Debt Securities of any series that are redeemable before their
Maturity shall be redeemable in accordance with their terms and (except as
otherwise specified pursuant to SECTION 301 for Debt Securities of any series)
in accordance with this Article.

SECTION 1202.  ELECTION TO REDEEM; NOTICE TO TRUSTEE.

                 The election of the Company to redeem any Debt Securities 
shall be evidenced by a Board Resolution.  The Company shall, at least 60 days
prior the Redemption Date fixed by the Company (unless a shorter notice shall
be satisfactory to the Trustee), notify the Trustee: (a) of such Redemption
Date and of the principal amount of Debt Securities of such series to be
redeemed; (b) the Redemption Price; (c) the Place or Places of Payment where
the Debt Securities are to be surrendered for the payment of the Redemption
Price; and (d) that payment will be made by the Paying Agent (if the Trustee is
not the Paying Agent) upon presentation and surrender of such Debt Securities. 
In  the case of any redemption of Debt Securities prior to the expiration  of
any restriction on such redemption provided in the terms of such Debt 
Securities or elsewhere in this Indenture, the Company shall furnish the
Trustee with an Officer's Certificate evidencing compliance with such
restrictions.
        




                                       64

<PAGE>   70
SECTION 1203.  SELECTION BY TRUSTEE OF DEBT SECURITIES TO BE REDEEMED.

                 If less than all the Debt Securities of any series are to be
redeemed at the election of the Company, the particular Debt Securities to be
redeemed shall be selected not more than 60 days prior to the Redemption Date
by the Trustee, from the Outstanding Debt Securities of such series not
previously called for redemption, by such method as the Trustee shall deem fair
and appropriate and which may provide for the selection for redemption of
portions of the principal amount of Debt Securities of such series. The
portions of the principal amount of Debt Securities so selected for partial
redemption shall be equal to the minimum authorized denominations for Debt
Securities of such series pursuant to SECTION 302 in the Currency in which the
Debt Securities of such series are denominated or any integral multiple
thereof, except as otherwise set forth in the applicable form of Debt
Securities.  In any case where more than one Debt Security of such series is
registered in the same name, the Trustee in its discretion may treat the
aggregate principal amount so registered as if it were represented by one Debt
Security of such series.

                 In the case of any Debt Securities selected for partial
redemption, the Trustee shall promptly notify the Company in writing of 
the Debt Securities selected for redemption and the principal amount thereof 
to be redeemed.

                 For all purposes of this Indenture, unless the context
otherwise requires, all provisions relating to the redemption of Debt
Securities shall relate, in the case of any Debt Security redeemed or to be
redeemed only in part, to the portion of the principal amount of such Debt
Security that has been or is to be redeemed.

SECTION 1204.  NOTICE OF REDEMPTION.

                 Notice of redemption shall be given by the Company, or at the
Company's request, by the Trustee in the name and at the expense of the
Company, not less than 30 days and not more than 60 days prior to the
Redemption Date to the Holders of Debt Securities of any series to be redeemed
in whole or in part pursuant to this ARTICLE TWELVE, in the manner provided in
SECTION 105.  Any notice so given shall be conclusively presumed to have been
duly given, whether or not the Holder receives such notice.  Failure to give
such notice, or any defect in such notice to the Holder of any Debt Security of
a series designated for redemption, in whole or in part, shall not affect the
sufficiency of any notice of redemption with respect to the Holder of any other
Debt Security of such series.

                 All notices of redemption shall state:

                 (1)      the Redemption Date,

                 (2)      the Redemption Price,





                                       65

<PAGE>   71
                 (3)      that Debt Securities of such series are being
         redeemed by the Company pursuant to provisions contained in this
         Indenture or the terms of the Debt Securities of such series or a
         supplemental indenture establishing such series, if such be the case,
         together with a brief statement of the facts permitting such
         redemption,

                 (4)      if less than all Outstanding Debt Securities of any
         series are to be redeemed, the identification (and, in the case of
         partial redemption, the principal amounts) of the particular Debt
         Securities to be redeemed,

                 (5)      that on the Redemption Date the Redemption Price will
         become due and payable upon each such Debt Security to be redeemed,
         and that interest thereon, if any, shall cease to accrue on and after
         said date, and

                 (6)      the Place or Places of Payment where such Debt
         Securities are to be surrendered for payment of the Redemption Price.

SECTION 1205.  DEPOSIT OF REDEMPTION PRICE.

                 On or prior to the Redemption Date for any Debt Securities,
the Company shall deposit with the Trustee or with a Paying Agent (or, if the
Company is acting as its own Paying Agent, segregate and hold in trust as
provided in SECTION 1103) an amount of money in the Currency or Currencies in
which such Debt Securities are denominated (except as provided pursuant to
SECTIONS 301 or 310) sufficient to pay the Redemption Price of such Debt 
Securities or any portions thereof that are to be redeemed on that date.

SECTION 1206.  DEBT SECURITIES PAYABLE ON REDEMPTION DATE.

                 Notice of redemption having been given as aforesaid, any Debt
Securities so to be redeemed shall, on the Redemption Date, become due and
payable at the Redemption Price in the Currency in which the Debt Securities of
such series are payable (except as otherwise specified pursuant to SECTIONS 301
or 310), and from and after such date (unless the Company shall default in the
payment of the Redemption Price) such Debt Securities shall cease to bear
interest.  Upon surrender of any such Debt Security for redemption in
accordance with said notice, such Debt Security shall be paid by the Company at
the Redemption Price; provided, however, that, unless otherwise specified as
contemplated by SECTION 301, installments of interest on Debt Securities that
have a Stated Maturity on or prior to the Redemption Date for such Debt
Securities shall be payable according to the terms of such Debt Securities and
the provisions of SECTION 307.

                 If any Debt Security called for redemption shall not be so
paid upon surrender thereof for redemption, the principal (and premium, if any)
shall, until paid, bear interest from the Redemption Date at the rate
prescribed therefor in the Debt Security.





                                       66

<PAGE>   72
SECTION 1207.  DEBT SECURITIES REDEEMED IN PART.

                 Any Debt Security that is to be redeemed only in part shall be
surrendered at the Corporate Trust Office or such other office or agency of the
Company as is specified pursuant to SECTION 301 with, if the Company, the
Security Registrar or the Trustee so requires, due endorsement by, or a written
instrument of transfer in form satisfactory to the Company, the Security
Registrar or the Trustee duly executed by, the Holder thereof or his attorney
duly authorized in writing, and the Company shall execute, and the Trustee
shall authenticate and deliver to the Holder of such Debt Security without
service charge, a new Debt Security or Debt Securities of the same series, of
like tenor and form, of any authorized denomination as requested by such Holder
in aggregate principal amount equal to and in exchange for the unredeemed
portion of the principal of the Debt Security so surrendered.  In the case of a
Global Note providing appropriate space for such notation, at the option of 
the Holder thereof, the Security Registrar, in lieu of delivering a new Global 
Note or Global Notes as aforesaid, may make a notation on such Debt Security 
of the payment of the redeemed portion thereof.


                                ARTICLE THIRTEEN

                                   DEFEASANCE

SECTION 1301.  APPLICABILITY OF ARTICLE.

                 If, pursuant to SECTION 301, provision is made for the
defeasance of Debt Securities of a series, and if the Debt Securities of such
series are denominated and payable only in Dollars then the provisions of this 
Article shall be applicable.   Defeasance provisions, if any, for Debt 
Securities denominated in a Foreign Currency or Currencies may be specified 
pursuant to SECTION 301.

SECTION 1302.  DEFEASANCE UPON DEPOSIT OF MONEYS OR U.S. GOVERNMENT
OBLIGATIONS.

                 At the Company's option, either (a) the Company shall be
deemed to have been Discharged (as defined below) from its obligations with
respect to Debt Securities of any series on the 91st day after the applicable
conditions set forth below have been satisfied or (b) the Company shall cease
to be under any obligation to comply with any term, provision or condition set
forth in SECTION 901 with respect to Outstanding Debt Securities of any series
(and, if so specified pursuant to SECTION 301, any other restrictive covenant
added for the benefit of such series pursuant to SECTION 301) at any time after
the applicable conditions set forth below have been satisfied:

                 (1)      the Company shall have deposited or caused to be
         deposited irrevocably with the Trustee as trust funds in trust,
         specifically pledged as security for, and dedicated solely to, the
         benefit of the Holders of the Outstanding Debt Securities of such
         series (i) money in an amount, or (ii) U.S. Government Obligations (as
         defined below) which





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<PAGE>   73
                
         through the payment of interest and principal in respect thereof in
         accordance with their terms will provide, not later than one day
         before the due date of any payment, money in an amount, or (iii) a
         combination of (i) and (ii), sufficient, in the opinion  of a
         nationally recognized firm of independent public accountants expressed
         in a written certification thereof delivered to the Trustee, to pay
         and discharge each installment of principal (including any mandatory
         sinking fund payments) of and premium, if any, and interest on, the
         Outstanding Debt Securities of such series on the dates such
         installments of interest or principal and premium are due;

                 (2)      such deposit will not result in a breach or violation
         of, or constitute a default under, this Indenture or any other
         agreement or instrument to which the Company is a party or by which it
         is bound;

                 (3)      if the Debt Securities of such series are then listed
         on any national securities exchange, the Company shall have delivered
         to the Trustee an Opinion of Counsel to the effect that the Company's
         exercise of its option under this Section would not cause such Debt
         Securities to be delisted;

                 (4)      an Officer's Certificate shall have been delivered to
         the Trustee stating that no Event of Default or event (including such
         deposit) which, with notice or lapse of time or both, would become an
         Event of Default with respect to the Debt Securities of such series
         shall have occurred and be continuing on the date of such deposit and
         the Company shall have delivered an Officers Certificate to the
         Trustee on the 91st day after the date of such deposit stating that
         no Event of Default under SECTION 501(4) or SECTION 501(5) or event
         which with the giving of notice or lapse of time, or both, would
         become an Event of Default under SECTION 501(4) or SECTION 501(5)
         shall have occurred and be continuing on the 91st day after such date;
         and

                 (5)      the Company shall have delivered to the Trustee an
         Opinion of Counsel to the effect that the Holders of the Debt
         Securities of such series will not recognize income, gain or loss for
         federal income tax purposes as a result of such deposit, defeasance or
         Discharge.

                 "Discharged" means that the Company shall be deemed to have
paid and discharged the entire indebtedness represented by, and obligations
under, the Debt Securities of such series and to have satisfied all the
obligations under this Indenture relating to the Debt Securities of such series
(and the Trustee, at the expense of the Company, shall execute proper
instruments acknowledging the same), except (A) the rights of Holders of Debt
Securities of such series to receive, from the trust fund described in clause
(1) above, payment of the principal of (and premium, if any) and interest on
such Debt Securities when such payments are due, (B) the Company's obligations
with respect to the Debt Securities of such series under SECTIONS 304, 305,
306, 1103 and 1303 and with respect to the Trustee under SECTION 607 and 
(C) the rights, powers, trusts, duties and immunities of the Trustee hereunder
including those pursuant to SECTION 607 hereof.

                 "U.S. Government Obligations" means securities that are (i)
direct obligations of the United States of America for the payment of which its
full faith and credit is pledged, or (ii) obligations of a Person controlled or
supervised by and acting as an agency or instrumentality





                                       68

<PAGE>   74
of the United States of America the timely payment of which is unconditionally
guaranteed as a full faith and credit obligation by the United States of
America, which, in either case under clauses (i) or (ii), are not callable or
redeemable at the option of the issuer thereof, and shall also include a
depository receipt issued by a bank or trust company as custodian with respect
to any such U.S. Government Obligation or a specific payment of interest on or
principal of any such U.S. Government Obligation held by such custodian for the
account of the holder of a depository receipt; provided that (except as
required by law) such custodian is not authorized to make any deduction from
the amount payable to the holder of such depository receipt from any amount
received by the custodian in respect of the U.S. Government Obligation or the
specific payment of interest on or principal of the U.S. Government Obligation
evidenced by such depository receipt.

SECTION 1303.  DEPOSIT MONEYS AND U.S. GOVERNMENT OBLIGATIONS TO BE HELD IN
TRUST.

                 All moneys and U.S. Government Obligations deposited with the
Trustee pursuant to SECTION 1302 in respect of Debt Securities of a series
shall be held in trust and applied by it, in accordance with the provisions of
such Debt Securities and this Indenture, to the payment, either directly or
through any Paying Agent (including the Company acting as its own Paying Agent)
as the Trustee may determine, to the Holders of such Debt Securities, of all
sums due and to become due thereon for principal (and premium, if any) and
interest, if any, but such money need not be segregated from other funds except
to the extent required by law.

SECTION 1304.  REPAYMENT TO COMPANY.

                 The Trustee and any Paying Agent shall promptly pay or return
to the Company upon Company Request any moneys or U.S. Government Obligations
held by them at any time that are not required for the payment of the principal
of (and premium, if any) and interest on the Debt Securities of any series for
which money or U.S. Government Obligations have been deposited pursuant to
SECTION 1302, provided that the Trustee may, at its option, request a written
certification of a nationally recognized firm of independent public accountants
certifying what amount, if any, of moneys or U.S. Government Obligations
deposited pursuant to Section 1302 is not required for the payment of the
principal of (and premium, if any) and interest on the Debt Securities of any
series.

                 The provisions of the last paragraph of SECTION 1103 shall
apply to any money held by the Trustee or any Paying Agent under this Article
that remains unclaimed for two years after the Maturity of any series of Debt
Securities for which money or U.S. Government Obligations have been deposited
pursuant to SECTION 1302.

SECTION 1305. REINSTATEMENT.

                 If the Trustee is unable to apply any money in accordance with
this ARTICLE THIRTEEN by reason of any legal proceeding or by reason of any
order or judgment of any court or governmental authority enjoining, restraining
or otherwise prohibiting such application, the Company's obligations under this
Indenture and the Debt Securities of such series shall be revived and
reinstated as though no deposit had occurred pursuant to this ARTICLE THIRTEEN
until such time as the Trustee is permitted to apply all such money in
accordance with this ARTICLE THIRTEEN; provided, however, that if the Company
has made any payment of interest on or principal of (and premium, if any, on),
any Debt Securities of such series because of the





                                       69

<PAGE>   75
reinstatement of its obligations, the Company shall be subrogated to the rights
of the Holders of such series of Debt Securities to receive such payment from
the money held by the Trustee.





                                       70

<PAGE>   76
                 IN WITNESS WHEREOF, the parties hereto have caused this
Indenture to be duly executed, and their respective corporate seals to be
hereunto affixed and attested, all as of the day and year first above written.


                                     KIRBY CORPORATION


                                     By: ___________________________________
                                     Print Name: ___________________________
                                     Title: ________________________________
                    







                                     TEXAS COMMERCE BANK NATIONAL
                                     ASSOCIATION, as Trustee


                                     By: ___________________________________
                                     Print Name: ___________________________
                                     Title: ________________________________





                                       71

<PAGE>   77
STATE OF         )
                 )       ss:
COUNTY OF        )


                 On the ____ day of December, 1994, before me personally came
__________________________________ to me known, who, being by me duly sworn,
did depose and say that he is _______________________________________ of Kirby
Corporation, one of the corporations described in and which executed the
foregoing instrument; that he knows the seal of said corporation; that the seal
affixed to said instrument is such corporate seal; that it was so affixed by
authority of the Board of Directors of said corporation, and that he signed his
name thereto by like authority.


                                               ______________________________
                                                        Notary Public        
                                               

SEAL



STATE OF         )
                 )       ss:
COUNTY OF        )


                 On the ____ day of December, 1994, before me personally came
_______________________________ to me known, who, being by me duly sworn, did
depose and say that he/she is __________________________________ of Texas
Commerce Bank National Association one of the entities described in and which
executed the foregoing instrument; that he knows the seal of said corporation;
that the seal affixed to said instrument is such corporate seal; that it was so
affixed by authority of the Board of Directors of said association, and that he
signed his name thereto by like authority.


                                               ______________________________
                                                        Notary Public        


SEAL





                                       72



<PAGE>   1
                               December 1, 1994

Kirby Corporation
1775 St. James Place
Suite 300
Houston, Texas 77056

         Re:   Offering of Debt Securities of Kirby Corporation

Gentlemen:

         On October 27, 1994, Kirby Corporation, a Nevada corporation (the
"Company"), filed with the Securities and Exchange Commission a Registration
Statement on Form S-3 (Registration No. 33-56195) (the "Registration 
Statement") under the Securities Act of 1933, as amended (the "Act").  Such
Registration Statement relates to the proposed issuance from time to time of up
to an aggregate of $250,000,000 principal amount of debentures, notes and/or
other unsecured evidences of indebtedness of the Company (the "Debt
Securities").  The Debt Securities shall  be issued from time to time pursuant
to an Indenture (the "Indenture") to be entered into between the Company and
Texas Commerce Bank National Association, as Trustee  (the "Trustee").  We have
acted as counsel to the Company in connection with  the preparation and filing
of the Registration Statement and the issuance and sale of the Debt Securities.
        
     In connection therewith, we have examined and relied upon the original or
copies, certified to our satisfaction, of (i) the Restated Articles of
Incorporation and the Bylaws of the Company,
 each as amended, (ii) copies of
resolutions of the Board of Directors of the Company authorizing the offering
and the issuance of the Debt Securities to be sold by the Company and related
matters, (iii) the Registration Statement, and all exhibits thereto, (iv) the
Indenture, and (v) such other documents and instruments as we have deemed
necessary for the expression of the opinions herein contained.  In making the
foregoing examinations, we have assumed the genuineness of all signatures and
the authenticity of all documents submitted to us as originals, and the
conformity to original documents of all documents submitted to us as certified
or photostatic copies.  As to various questions of fact material to this
opinion, we have relied, to the extent we deem reasonably appropriate, upon
representations or certificates of officers or directors of the Company and
upon documents, records and instruments furnished to us by the Company, without
independent check or verification of their accuracy.

     Based upon the foregoing examination, we are of the opinion that when all
necessary proceedings have been taken by the Board of Directors or the
authorized officers of the Company in connection with the authorization,
issuance and sale of the Debt Securities of a particular series and related
matters, the Debt Securities of such series, when duly executed on behalf of
the Company and authenticated by the Trustee and issued and delivered pursuant
to the Indenture against payment to the Company of the authorized consideration
therefor, will be duly






<PAGE>   2
Kirby Corporation
November 14, 1994
Page 2




authorized and validly issued and will be binding obligations of the Company in
accordance with their terms, subject to the extent that rights to
indemnification thereunder may be limited by federal or state securities laws
and policies embodied therein or to the extent that such obligations are
subject to or affected or limited by (i) applicable liquidation,
conservatorship, bankruptcy, insolvency, reorganization, fraudulent conveyance,
moratorium or other laws affecting creditors' rights or the collection of
debtors' obligations generally from time to time in effect or (ii) general
principles of equity (whether enforceability is considered in a proceeding in
equity or at law), including the qualification that the availability of the
remedies of specific performance or injunctive relief or other equitable
remedies is subject to the discretion of the court before which any such
proceeding therefor may be brought and including standards of good faith, fair
dealing and reasonableness that may be applied by a court to the exercise of
certain rights and remedies.  Further, we express no opinion as to the
following: (i) whether a court would grant any remedy sought with respect to
immaterial breaches or to the extent any purchaser has acted in bad faith in
exercising remedies; or (ii) whether a court would grant a particular remedy
provided for in the Debt Securities or the Indenture as opposed to another
remedy provided for therein or at law or in equity.  With respect to matters
governed by New York law, we have relied on the opinion of Andrews & Kurth 
L.L.P. to the Company, dated as of the date hereof, a copy of which is attached.

     We hereby consent to the filing of this opinion as an exhibit to the
Registration Statement and to the use of our name under the caption "Legal
Matters" in the Prospectus forming part of the Registration Statement.  In
giving such consent, we do not admit that we come within the category of
persons whose consent is required by Section 7 of the Act or the rules and
regulations of the Commission thereunder.

     We advise you that Henry Gilchrist, who is the Secretary and an Advisory
Director of the Company, is a shareholder of this firm.


                                        Very truly yours,

                                        JENKENS & GILCHRIST,
                                          a Professional Corporation



                                        By: /S/ HENRY GILCHRIST

                                                Henry Gilchrist
    
HG:GWC:kb






<PAGE>   3
                               December 1, 1994


Kirby Corporation
1775 St. James Place
Suite 300
Houston, Texas 77056

Gentlemen:


        We have acted as counsel to Merrill Lynch, Pierce, Fenner & Smith
Incorporated, Salomon Brothers Inc and Wertheim Schroder & Co. Incorporated in
connection with the preparation and filing with the Securities and Exchange
Commission (the "Commission") under the Securities Act of 1933, as amended, of
the registration statement on Form S-3 (No. 33-56195) filed by Kirby
Corporation, a Nevada corporation (the "Company") with the Commission (such
registration statement being hereinafter referred to as the "Registration
Statement") relating to the offering from time to time of the Company's
unsecured debt securities (the "Debt Securities") having an aggregate initial
public offering or purchase price of up to U.S. $250,000,000 or the equivalent
thereof in one or more other currencies, including composite currencies as set
forth in the Registration Statement. The Debt Securities are to be issued in
one or more series in accordance with the provisions of the indenture (the
"Indenture") to be entered into beween the Company and Texas Commerce Bank
National Association, as trustee (the "Trustee").

        In arriving at the opinions expressed below, we have examined the
Registration Statement, the form of Indenture filed as Exhibit 4.3 to the
Registration Statement and the original or copies certified or otherwise
identified to our satisfaction of such other instruments and other certificates
of public officials, officers and representatives of the Company and such other
persons, and we have made such investigations of law, as we have deemed
appropriate as a basis for the opinions expressed below. In rendering the
opinions expressed below, we have with your permission and without independent
investigation:

                (a)      assumed that (i) the Company is a corporation validly
        existing and in good standing under the laws of the State of Nevada and
        the Trustee is a national banking association validly existing and in
        good standing under the laws of the United States of America, (ii) the
        Indenture has been duly authorized, executed and delivered by each of
        the Company and the Trustee, (iii) the Indenture constitutes a valid
        and binding obligation of the Trustee, enforceable against the Trustee
        in accordance with its terms, (iv) no approval, authorization or other
        action by, or (except as covered by our assumptions in clauses (i),
        (ii) or (iii) of clause (e) below) registration, filing or declaration
        with, any governmental authority, court or arbitrator, is or will be
        required in connection with the execution, delivery or performance by
        the Company or the Trustee of the Indenture or any Debt Securities, (v)
        neither the execution, delivery and performance by the Company of the
        Indenture and the Debt Securities of each future series, nor the offer,
        issue, sale and delivery of any such Debt Securities, will violate any
        provision of the charter or bylaws of the Company, or any other legal
        requirement now or hereafter in effect binding upon or affecting the
        Company or its operations or properties in such manner as to affect
        adversely the validity or enforceability of the Indenture or such Debt
        Securities and (vi) the execution, delivery and performance by the
        Trustee of the Indenture will not violate any legal requirement now or
        hereafter in effect binding upon or affecting the Trustee on its
        operations or properties in such manner as to afftect adversely the
        validility or enforceability of the Indenture;
        
                (b)      assumed (i) that the signatures on all documents that
        we have examined are genuine, (ii) the conformity to the originals of
        all documents supplied to us as certified or photostatic or faxed
        copies, and (iii) the authenticity of the originals of such
        documents;
        
                (c)      assumed that (i) all documents in respect of which
        forms were filed with the Commission as exhibits to the Registration
        Statement will conform in all material respects to the forms thereof
        that we have examined and (ii) all Debt Securities to be issued by the
        Company will be in substantially the form of the drafts submitted to us
        by the Company, with all blanks duly completed and with such additions,
        deletions and modifications as are required to comply with applicable
        law and the terms of the Indenture and to reflect the terms of the
        particular series of Debt Securities and;
        
                (d)      assumed that (i) the Registration Statement, and any
        amendments thereto (including post-effective amendments), will have
        become effective, (ii) a Prospectus Supplement will have been prepared
        and filed with the Commission describing the Securities offered thereby,
        (iii) all Securities will be issued and sold in compliance with the
        applicable federal and state securities laws and in the manner stated
        in the Registration Statement and the appropriate Prospectus Supplement
        and (iv) the applicable distribution, underwriting or similar agreement
        pursuant to which such Debt Securities are to be sold has been duly
        authorized, executed and delivered by each underwriter, dealer or other
        party thereto.

        Based on the foregoing, and subject to the limitations and exceptions
set forth below, it is our opinion that:

        1.      The Indenture is a valid and binding obligation of the Company
enforceable against the Company in accordance  with its terms subject to
applicable bankruptcy, insolvency (including, without limitation, all laws
relating to fraudulent transfer), reorganization, moratorium and simliar laws
affecting creditors' rights generally, to general principles of equity
(regardless of whether enforcement is sought in a proceeding in equity or at
law) and to possible judicial action giving effect to governmental actions or
foreign laws affecting creditors' rights.

        2.      When (i) the issuance, execution and delivery by the Company of
the Debt Securities of a series have been duly authorized by all necessary 
corporate action of the Company in accordance with applicable law and the 
provisions of the Indenture, (ii) such Debt Securities have been duly 
authenticated by the 








<PAGE>   4
Kirby Corporation
December 1, 1994
Page 2

Trustee in accordance with applicable law and the provisions of the Indenture 
and (iii) the applicable distribution, underwriting or similar agreement
pursuant to which such Debt Securities are to be sold has been duly authorized,
executed and delivered by the Company under the laws of the State of Nevada and
such Debt Securities are executed and delivered by the Company and issued in
accordance  with the provisions of such agreement upon payment or delivery of
the consideration specified therein for such Debt Securities, such Debt
Securities will constitute valid and binding obligations of the Company,
enforceable against the Company in accordance with their terms, entitled to the
benefits of the Indenture, subject to applicable bankruptcy, insolvency
(including, without limitation, all laws relating to fraudulent transfer,
reorganization, moratorium and similar laws effecting creditors rights
generally, to general principles of equity (regardless of whether enforcement
is sought in a proceeding in equity or at law) and to possible judicial action
giving effect to governmental actions or foreign laws affecting creditors'
rights.

        With respect to our opinions expressed in paragraph (2) above as they
relate to Debt Securities denominated in a currency other the U.S. dollars, we
note that effective enforcement of a foreign currency claim in the New York
State courts or the federal courts sitting in the State of New York may be
limited by requirements that the claim (or a foreign currency judgment in
respect of such claim) be converted into U.S. dollars at the rate of exchange
prevailing on a specified date. We express no opinion as to whether a federal
court sitting in the State of New York would award a judgment in a currency
other than U.S. dollars. Additionally, with respect to our opinions expressed
in paragraph (2), we have assumed that any Indexed Note (as such term is
defined in the Prospectus Supplement referred to above) will comply with the 
United States Commodity Exchange Act of 1922, as amended, and the rules, 
regulations and orders of the Commodity Futures Trading Commission promulgated 
thereunder and with any applicable provisions of state law.

        We express no opinion other than as to the law of the State of New
York.

        This opinion is being furnished to Kirby Corporation in connection
with the opinion to be rendered by Jenkens & Gilchrist, a Professional
Corporation to the Company and filed with the Commission as Exhibit 5.1 to the
Registration Statement. This opinion speaks as of its date, and we undertake no
duty to advise you as to changes in fact or law coming to our attention after
the date hereof. This opinion may not be used, quoted, published, circulated or
relied upon by any person for any purposes without our prior written consent
except that Jenkens & Gilchrist, a
        



<PAGE>   5
Kirby Corporation
December 1, 1994
Page 3




Professional Corporation, may rely on this opinion as if it were addressed to
it for purposes of rendering its opinion to be filed as Exhibit 5.1 to the
Registration Statement. In this regard, we do not admit that we are "experts"
under the Securities Act of 1933, as amended, or the rules and regulations of
the Commission issued thereunder, with respect to any part of the Registration
Statement, including such opinion of Jenkens & Gilchrist, a Professional
Corporation.




                                              Very truly yours,

                                              ANDREWS & KURTH L.L.P.

1210/2281