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                                                                  EXHIBIT 10(j)



                               FIRST AMENDMENT TO
               AMENDED AND RESTATED OMNIBUS ACQUISITION AGREEMENT
                   AND AMENDED AND RESTATED BASKET AGREEMENT

         This First Amendment to Amended and Restated Omnibus Acquisition
Agreement and Amended and Restated Basket Agreement dated March 31, 1992 is
entered into among the parties to that certain Amended and Restated Omnibus
Acquisition Agreement (the "Omnibus Agreement") dated November 13, 1989, by and
among Cabot Corporation ("Cabot"), Cabot Transmission Corporation ("Seller")
and American Oil and Gas Corporation ("AOG"), and that certain Amended and
Restated Basket Agreement dated as of November 13, 1989, as amended and
restated as of June 30, 1990, by and among Seller, Cabot, AOG and American
Pipeline Company (the "Basket Agreement");

         WHEREAS, the parties to the Omnibus Agreement and the Basket Agreement
believe that it is mutually beneficial and desire to amend certain provisions
of each such Agreement;

         NOW, THEREFORE, the parties hereto agree as follows:

         Section 1. Amendments to Omnibus Agreement. The Omnibus Agreement is
hereby amended to delete Item No. 1 to Schedule 11.07 of the Omnibus Agreement.
The effect of such deletion shall be that Cabot shall no longer indemnify AOG,
the Acquired Companies (as defined in the Omnibus Agreement) and the other
enumerated persons and entities under Section 11.07(A) of the Omnibus Agreement
for those matters described in Item No. 1 to Schedule 11.07 of the Omnibus
Agreement.

         Section 2. Amendments to Basket Agreement.

         (a) Section 2.6 of the Basket Agreement, which defines the term
"Basket Payments," is hereby amended as follows:

                  (i) by deleting the word "and" immediately prior to clause
(iii) of Section 2.6 and inserting a comma in its place;

                 (ii) by replacing the period at the end of Section 2.6 with a
comma and inserting the following at the end of Section 2.6:

                           "(iv) all payments made after March 31, 1992, with
                 respect to all periods prior to November 13, 1989, by AOG or
                 its subsidiaries or affiliates to potential claimants
                 referenced in Schedule I to the First Amendment


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                  to Amended and Restated Omnibus Acquisition Agreement and
                  Amended and Restated Basket Agreement dated March 31, 1992
                  (the "First Amendment"), their subsidiaries, affiliates or
                  successors in interest ("Schedule I Claimants") in respect of
                  any potential claims (including possible claims for higher
                  prices and potential claims for refund) described in such
                  Schedule I (the "Schedule I Claims"), under the respective
                  contracts described in Schedule I in excess of the prices
                  previously paid to such Schedule I Claimants by AOG, its
                  subsidiaries, affiliates or predecessors in interest,
                  including payments arising out of any applicable tax
                  reimbursements and/or royalty claims which may arise as a
                  result of such payments of higher prices, (v) all payments
                  made after March 31, 1992, with respect to all periods after
                  November 12, 1989, by AOG, its subsidiaries or affiliates to
                  Schedule I Claimants in respect of the Schedule I Claims for
                  amounts in excess of (x) the Section l06(b)(1)(A) gas price
                  in effect from time to time under the Natural Gas Policy Act
                  of 1978 and related regulations through December 31, 1992 and
                  (y) that price which is paid in good faith for periods after
                  December 31, 1992 to the Schedule I Claimants under the
                  respective gas contracts described in Schedule I, including
                  any payment arising out of applicable tax reimbursement
                  obligations and/or royalty claims which may arise as a result
                  of such payments of higher prices, (vi) any payments arising
                  out of royalty claims, which payments are made after March
                  31, 1992 by AOG, its subsidiaries or affiliates with respect
                  to Schedule I Claims which were settled prior to March 31,
                  1992 with Cabot's approval but which settlements expressly
                  did not resolve the royalty claim issues, (vii) all payments
                  or refunds (including without limitation payments arising out
                  of royalty claims related in any way to such payments) which
                  AOG, its subsidiaries, or affiliates may become legally
                  obligated to make in respect


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                  of the Schedule I Claims and not covered by clauses (iv)
                  through (vi) hereof, and (viii) all outside legal,
                  professional or other out-of-pocket expenses or costs
                  incurred by AOG, its subsidiaries or affiliates after March
                  31, 1992, in connection with the investigation, analysis,
                  negotiation, litigation, arbitration or settlement of any of
                  the Schedule I Claims, potential Schedule I Claims or any and
                  all of the matters identified in clauses (iv) through (vii)
                  hereof, including without limitation the costs of preparing
                  gas reserve reports covering gas production and reserves
                  produced under the respective gas contracts described in
                  Schedule I hereto.

         (b) Section 2.3 of the Basket Agreement, which defines the term
"Basket Collections," is hereby amended as follows:

                  (i)      by deleting the word "and" at the end of the first
clause (ii) of Section 2.3;

                  (ii)     by replacing the period at the end of the first
clause (iii) of Section 2.3 with a semicolon followed by the word "and"; and

                  (iii)    adding the following immediately after the first
clause (iii) of Section 2.3:

                           "(iv) the amortization in the actual weighted
                  average cost of gas used in billing customers or other
                  recovery by flow-through to customers or liquidation or
                  recovery in any other manner of the payments, refunds,
                  expenses or costs described in clauses (iv) through (viii) of
                  Section 2.6 hereof.

         (c) Section 7 of the Basket Agreement is hereby amended by inserting
the following clause immediately following the term "Take or Pay Claims" in
each place where such term appears in Section 7:

                  "or Schedule I Claims (as such term is defined in Section
                  2.6), together with all related claims described in clauses
                  (iv) through (viii) of Section 2.6 hereof"

         Section 3. Effect of Amendments. The respective amendments to the
Omnibus Agreement and Basket Agreement set forth in this First Amendment (i)


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shall be effective as of the date hereof and (ii) shall remain subject to all
other effective provisions of the agreement being amended hereby.

         Section 4. Counterparts. This First Amendment may be executed by the
parties hereto in multiple counterparts, all of which counterparts, taken
together, shall constitute one and the same agreement.



                                      CABOT CORPORATION



                                      By:
                                             ----------------------------------
                                      Name:
                                             ----------------------------------
                                      Title:
                                             ----------------------------------


                                      CABOT TRANSMISSION CORPORATION



                                      By:      /s/ Robert A. [NOT LEGIBLE]
                                               --------------------------------
                                      Name:    Robert A. [NOT LEGIBLE]
                                               -------------------------------
                                      Title:   Vice President
                                               -------------------------------


                                      AMERICAN OIL AND GAS CORPORATION



                                      By:      /s/ Thomas H. Fanning
                                               --------------------------------
                                      Name:    Thomas H. Fanning
                                               --------------------------------
                                      Title:   Vice President
                                               --------------------------------


                                      AMERICAN PIPELINE COMPANY


                                      By:      /s/ Thomas H. Fanning
                                               --------------------------------
                                      Name:    Thomas H. Fanning
                                               --------------------------------
                                      Title:   Vice President
                                               --------------------------------



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