Exhibit 10.9.3
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                               EASTERN ENTERPRISES

                          Amendment of Trust Agreement




         Instrument of amendment  dated February 25, 1998 by and between Eastern
Enterprises ("Eastern") and Key Trust Company of Ohio, N.A. (the "Trustee"):

         WHEREAS  Eastern  and the  Trustee  are  parties  to a trust  agreement
originally  dated  January  29,  1987 and  subsequently  amended,  including  to
substitute the current  Trustee as trustee of the trust  established  under such
agreement (as heretofore amended, the "Trust Agreement"); and

         WHEREAS  Eastern wishes to amend the Trust Agreement to provide for the
payment of benefits under a recently  established  Supplemental  Retirement Plan
for Certain Officers; and

         WHEREAS  Eastern has  reserved the right to make such  amendment  under
Section 10(a) of the Trust Agreement;

         NOW, THEREFORE, in consideration of these premises, the Trust Agreement
is hereby amended as follows, effective as of the date set forth above:

         1. The first "WHEREAS" clause is amended by deleting the words "and the
1994 Deferred  Compensation  Plan" and  replacing  them with the words "the 1994
Deferred  Compensation  Plan, and the  Supplemental  Retirement Plan for Certain
Officers".

         2. Section 1(b) is amended by deleting the words "or the 1994  Deferred
Compensation  Plan"  and  replacing  them  with the  words  "the  1994  Deferred
Compensation Plan, the Supplemental Retirement Plan for Certain Officers".

         3. Section 1(e) is amended by deleting the words "and the 1994 Deferred
Compensation  Plan)"  and  replacing  them  with the words  "the  1994  Deferred
Compensation Plan, and the Supplemental Retirement Plan for Certain Officers)".

         4.       Section 2 (a) is amended by adding the words "or in the 
Supplemental Retirement Plan for Certain Officers" immediately after the word
"SERP" and




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immediately before the portion of such subsection that begins: "; and further 
provided, that no such modification . . . ".

         IN WITNESS  WHEREOF,  Eastern  Enterprises  and the Trustee have caused
this instrument of amendment to be executed by their duly authorized officers as
of the date set forth above.


                                     EASTERN ENTERPRISES



                                     By: /s/ EASTERN ENTERPRISES
                                     ------------------------


                                     KEY TRUST COMPANY OF OHIO, N.A.



                                     By: /S/KEY TRUST COMPANY OF OHIO, N.A.
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