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                                                                 EXHIBIT 4(a)(8)

                                                                [CONFORMED COPY]
 
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                                  TENNECO INC.
 
                                      AND
 
                            THE CHASE MANHATTAN BANK
                            (NATIONAL ASSOCIATION),
 
                                                                      AS TRUSTEE
 
                              ------------------
 
                          TENTH SUPPLEMENTAL INDENTURE
 
                         DATED AS OF NOVEMBER 15, 1992
 
                                       TO
 
                                   INDENTURE
 
                           DATED AS OF MARCH 15, 1988
 
                              ------------------
 
                         PROVIDING FOR THE ISSUANCE OF
                             9% DEBENTURES DUE 2012
 
 
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  Tenth Supplemental Indenture dated as of November 15, 1992 between Tenneco
Inc., a corporation duly organized and existing under the laws of the State of
Delaware (hereinafter called the "Company"), and The Chase Manhattan Bank
(National Association), a national banking association existing under the laws
of the United States of America, as trustee (hereinafter called the
"Trustee").
 
  Whereas, the Company has heretofore executed and delivered to the Trustee an
indenture dated as of March 15, 1988 (hereinafter called the "Original
Indenture"), to provide for the issue of an unlimited amount of debentures,
notes and/or other debt obligations of the Company (hereinafter referred to as
the "Securities"), the terms of which are to be determined as set forth in
(S) 2.02 of the Original Indenture; and
 
  Whereas, (S) 12.01 of the Original Indenture provides, among other things,
that the Company and the Trustee may enter into indentures supplemental to the
Original Indenture for, among other things, the purpose of setting forth the
terms of Securities of any series; and
 
  Whereas, the Company desires to create a series of the Securities in an
aggregate principal amount of $150,000,000 to be designated the "9 %
Debentures due 2012" (the "Debentures"), and all action on the part of the
Company necessary to authorize the issuance of the Debentures under the
Original Indenture and this Tenth Supplemental Indenture has been duly taken;
and
 
  Whereas, all acts and things necessary to make the Debentures, when executed
by the Company and authenticated and delivered by the Trustee as in the
Indenture provided, the valid and binding obligations of the Company, and to
constitute these presents a valid and binding supplemental indenture and
agreement according to its terms, have been done and performed;
 
  Now, therefore, in consideration of the premises and of the mutual covenants
herein contained, and of the acceptance of this trust by the Trustee, and of
the sum of one dollar to the Company duly paid by the Trustee at the execution
and delivery of these presents, and of other valuable consideration the
receipt whereof is hereby acknowledged and in order to authorize the
authentication and delivery of and to set forth the terms of the Debentures,
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                                      2
 
  It is hereby covenanted, declared and agreed by and between the parties
hereto, for the benefit of holders of the Debentures issued under the
Indenture, as follows:
 
                                  ARTICLE 1.
 
                 Terms and Issuance of 9% Debentures Due 2012
 
  (S) 1.01. Issue of Debentures. A series of Securities which shall be
designated the "9% Debentures due 2012" shall be executed, authenticated and
delivered in accordance with the provisions of, and shall in all respects be
subject to, the terms, conditions and covenants of the Indenture, including
without limitation the terms set forth in this Tenth Supplemental Indenture
(including the form of Debentures set forth in (S) 1.02 hereof). The aggregate
principal amount of Debentures which may be authenticated and delivered under
the Indenture shall not, except as permitted by the provisions of (S)(S) 2.07,
2.08, 2.10, 2.11 or 3.02 of the Indenture, exceed $150,000,000. The entire
amount of Debentures may forthwith be executed by the Company and delivered to
the Trustee and shall be authenticated by the Trustee and delivered to or upon
the order of the Company pursuant to (S) 2.03 of the Indenture.
 
  (S) 1.02. Forms of Debentures and Authentication Certificate. The forms of
the Debentures and the Trustee's certificate of authentication shall be
substantially as follows:
 
                          [form of face of debenture]
 
                                 TENNECO INC.
 
                             9% DEBENTURE DUE 2012
 
No.                                                                    $
 
  Tenneco Inc., a corporation organized and existing under the laws of the
State of Delaware (hereinafter called the "Company," which term shall include
any successor corporation as defined in the Indenture hereinafter referred
to), for value received, hereby promises to pay to                or registered 
assigns, the sum of       Dollars on November 15, 2012, in any coin or currency 
of the United States of America which at the time of payment is legal tender for
the payment of public and private debts, and to pay to the registered holder
hereof as hereinafter provided interest thereon at the rate per annum specified
in the title hereof in like coin or currency, from the May 15
 
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or November 15 next preceding the date hereof to which interest has been paid,
unless the date hereof is a May 15 or November 15 to which interest on the
Debentures has been paid, in which case from the date hereof, or unless no
interest has been paid on the Debentures since the original issue date
(hereinafter referred to) of this Debenture, in which case from the original
issue date, semi-annually on May 15 and November 15 in each year, until
payment of said principal sum has been made or duly provided for, and to pay
interest on any overdue principal and (to the extent permitted by law) on any
overdue installment of interest at the rate of 9% per annum. Notwithstanding
the foregoing, when there is no existing default in the payment of interest on
the Debentures, if the date hereof is after April 30 or October 31 and prior
to the following May 15 or November 15, as the case may be, this Debenture
shall bear interest from such May 15 or November 15; provided, however, that
if the Company shall default in the payment of interest due on such May 15 or
November 15, then this Debenture shall bear interest from the May 15 or
November 15 to which interest has been paid or, if no interest has been paid
on the Debentures since the original issue date of this Debenture, from the
original issue date. The interest so payable on any May 15 or November 15
will, subject to certain exceptions provided in the Indenture hereinafter
referred to, be paid to the person in whose name this Debenture is registered
at the close of business on the April 30 or October 31, as the case may be,
next preceding such May 15 or November 15, or if such April 30 or October 31
is not a business day, the business day next preceding such April 30 or
October 31. Interest on this Debenture shall be computed on the basis of a
360-day year or twelve 30-day months. Both principal of and interest on this
Debenture are payable at the principal office of the Trustee in the Borough of
Manhattan, The City of New York, New York; provided, however, that payment of
interest may be made, at the option of the Company, by check mailed to the
address of the person entitled thereto as such address shall appear on the
Debenture register. The original issue date in respect of the Debentures is
November 24, 1992.
 
  ADDITIONAL PROVISIONS OF THIS DEBENTURE ARE CONTAINED ON THE REVERSE HEREOF
AND SUCH PROVISIONS SHALL FOR ALL PURPOSES HAVE THE SAME EFFECT AS THOUGH
FULLY SET FORTH AT THIS PLACE.
 
  This Debenture shall not be entitled to any benefit under the Indenture
hereinafter referred to, or become valid or obligatory for any purpose, until
the Trustee under the Indenture shall have signed the form of certificate of
authentication endorsed hereon.
 
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                                      4
 
  In Witness Whereof, Tenneco Inc. has caused this Instrument to be signed in
its name by its Chairman of the Board or its President or a Vice President,
and its corporate seal (or a facsimile thereof) to be hereto affixed and
attested by its Secretary or an Assistant Secretary.
 
Dated ..........................
 
                                   Tenneco Inc.
 
                                     By .......................................
                                                          Chairman of the Board
 
Attest:
 
 ................................
                      Secretary.
 
                        [form of reverse of debenture]
 
                                 TENNECO INC.
 
                             9% DEBENTURE DUE 2012
 
  This Debenture is one of a duly authorized issue of Debentures of the
Company known as its 9% Debentures due 2012 (herein called the "Debentures"),
limited to the aggregate principal amount of $150,000,000, all issued under
and equally entitled to the benefits of an Indenture (herein, together with
any amendments and supplements thereto, including without limitation the form
and terms of Securities issued pursuant thereto, called the "Indenture"),
dated as of March 15, 1988, executed by the Company to The Chase Manhattan
Bank (National Association) (herein, together with any successor thereto,
called the "Trustee"), as Trustee, to which Indenture reference is hereby made
for a statement of the rights thereunder of the Trustee and of the registered
holders of the Debentures and of the duties thereunder of the Trustee and the
Company.
 
  The Debentures are not subject to redemption by the Company prior to
maturity.
 
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                                      5
 
  The Indenture permits the Company to issue unsecured debentures, notes
and/or other evidences of indebtedness in one or more series ("Securities") up
to such principal amount or amounts as may be authorized in accordance with
the terms of the Indenture.
 
  To the extent permitted by, and as provided in, the Indenture, modifications
or alterations of the Indenture and of the rights and obligations of the
Company and of the holders of the Debentures may be made with the consent of
the Company and with the consent of the holders of not less than a majority in
principal amount of the Securities of all series then outstanding under the
Indenture (treated as a single class) which are affected by the modification
or amendment thereto; provided, however, that without the consent of the
holder hereof no such modification or alteration shall be made which will
affect the terms of payment of the principal of or interest on this Debenture.
 
  In case a default, as defined in the Indenture, shall occur, the principal
of all the Debentures at any such time outstanding under the Indenture may be
declared or may become due and payable, upon the conditions and in the manner
and with the effect provided in the Indenture. The Indenture provides that
such declaration may in certain events be waived by the holders of a majority
in principal amount of the Debentures outstanding in the case of payment
defaults on the Debentures and in certain other events by the holders of a
majority in principal amount of the Securities of all series then outstanding
under the Indenture (treated as a single class) which are affected thereby.
 
  The Indenture provides that no holder of any Debenture may enforce any
remedy under the Indenture except in the case of refusal or neglect of the
Trustee to act after notice of default and after request by the holders of a
majority in principal amount of the outstanding Debentures in certain events
(and in certain other events by the holders of a majority in principal amount
of the Securities of all series then outstanding under the Indenture, treated
as a single class, which are affected thereby) and the offer to the Trustee of
security and indemnity satisfactory to it; provided, however, that such
provision shall not prevent the holder hereof from enforcing payment of the
principal of or interest on this Debenture.
 
  The transfer of this Debenture is registrable by the registered holder
hereof, in person or by duly authorized attorney, at the agency of the Company
in the Borough of Manhattan, The City of New York, New York, on books of the
Company to be kept for that purpose at said agency, upon surrender and
cancellation of this Debenture and on presentation of a duly executed written
 
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                                      6
 
instrument of transfer, and thereupon a new Debenture or Debentures, of the
same aggregate principal amount and in authorized denominations, will be
issued to the transferee or transferees in exchange herefor; and this
Debenture, with or without other Debentures, may in like manner be exchanged
for one or more new Debentures of other authorized denominations but of the
same aggregate principal amount; all subject to the terms and conditions set
forth in the Indenture.
 
  The Company, the Trustee, any paying agent and any Registrar of the
Debentures may deem and treat the person in whose name this Debenture is
registered as the absolute owner hereof for all purposes whatsoever, and
neither the Company nor the Trustee nor any paying agent nor any Registrar of
the Debentures shall be affected by any notice to the contrary.
 
  No recourse shall be had for the payment of the principal of or the interest
on, this Debenture, or for any claim based hereon or on the Indenture, against
any incorporator, or against any stockholder, director or officer, as such,
past, present or future, of the Company, or 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, all
such liability, whether at common law, in equity, by any constitution, statute
or otherwise, of incorporators, stockholders, directors or officers being
released by every owner hereof by the acceptance of this Debenture and as part
of the consideration for the issue hereof, and being likewise released by the
terms of the Indenture; provided, however, that nothing herein or in the
Indenture contained shall be taken to prevent recourse to and the enforcement
of the liability, if any, of any stockholder or subscriber to capital stock of
the Company upon or in respect of shares of capital stock not fully paid up.
 
  All terms used in this Debenture which are defined in the Indenture shall
have the meanings assigned to them in the Indenture.
 
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                                      7
 
               [form of trustee's certificate of authentication]
 
  This Debenture is one of the 9% Debentures due 2012 described in the within-
mentioned Indenture.
 
                                   THE CHASE MANHATTAN BANK
                                     (National Association),
                                                                       Trustee,
 
                                       By.....................................
                                                   Authorized Officer.
 
                                  ARTICLE 2.
 
                                 Miscellaneous
 
  (S) 2.01. Execution as Supplemental Indenture. This Tenth Supplemental
Indenture is executed and shall be construed as an indenture supplemental to
the Original Indenture and, as provided in the Original Indenture, this Tenth
Supplemental Indenture forms a part thereof. Except as herein expressly
otherwise defined, the use of the terms and expressions herein is in
accordance with the definitions, uses and constructions contained in the
Original Indenture.
 
  (S) 2.02. Responsibility for Recitals, Etc. The recitals herein and in the
Debentures (except in the Trustee's certificate of authentication) shall be
taken as the statements of the Company, and the Trustee assumes no
responsibility for the correctness thereof. The Trustee makes no
representations as to the validity or sufficiency of this Tenth Supplemental
Indenture or of the Debentures. The Trustee shall not be accountable for the
use or application by the Company of the Debentures or of the proceeds
thereof.
 
  (S) 2.03. Provisions Binding on Company's Successors. All the covenants,
stipulations, promises and agreements in this Tenth Supplemental Indenture
contained by the Company shall bind its successors and assigns whether so
expressed or not.
 
  (S) 2.04. New York Contract. This Tenth Supplemental Indenture and each
Debenture shall be deemed to be a contract made under the laws of the State of
New York, and for all purposes shall be construed in accordance with the laws
of said State without regard to principles of conflicts of laws.
 
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  (S) 2.05. Execution and Counterparts. This Tenth Supplemental 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.
 
  In Witness Whereof, said Tenneco Inc. has caused this Tenth Supplemental
Indenture to be executed in its corporate name by its Chairman of the Board or
its President or one of its Vice Presidents, and said The Chase Manhattan Bank
(National Association) has caused this Indenture to be executed in its
corporate name by one of its Vice Presidents as of November 15, 1992.
 
                                   Tenneco Inc.
 
                                                 Robert T. Blakely
                                   By _________________________________________
                                                 Robert T. Blakely
                                               Senior Vice President
 
                                   The Chase Manhattan Bank
                                     (National Association)
 
                                                 C. J. Heinzelmann
                                   By _________________________________________
                                               Charles J. Heinzelmann
                                                   Vice President