Exhibit 10.23.3

                 THIRTY-SEVENTH AGREEMENT AMENDING
                 NEW ENGLAND POWER POOL AGREEMENT


     THIS THIRTY-SEVENTH AGREEMENT AMENDING NEW ENGLAND POWER POOL
AGREEMENT, dated as of August 15, 1998 ("Thirty-Seventh Agreement"), is
entered into by the signatory Participants to amend the New England Power
Pool Agreement (the "NEPOOL Agreement"), as amended.

     WHEREAS, the NEPOOL Agreement as in effect on December 1, 1996 was
amended and restated by the Thirty-Third Agreement Amending New England
Power Pool Agreement dated as of December 1, 1996 (the "Thirty-Third
Agreement") in the form of the Restated New England Power Pool Agreement
("Restated NEPOOL Agreement") attached to the Thirty-Third Agreement as
Exhibit A thereto, and the Thirty-Third Agreement also provided for the
NEPOOL Open Access Transmission Tariff ("Tariff") which is Attachment B to
the Restated NEPOOL Agreement; and

     WHEREAS, the Restated NEPOOL Agreement and the Tariff have
subsequently been amended by five supplements dated, respectively, as of
February 7, June 1, September 1, November 1 and December 31, 1997 and by
three additional amendatory agreements dated, respectively, as of September
1, 1997, November 15, 1997 and July 20, 1998; and

     WHEREAS, the signatories hereto desire to amend the Restated NEPOOL
Agreement, as  amended by the Thirty-Sixth Agreement Amending New England
Power Pool Agreement, dated July 20, 1998, to amend the definition of
"Power Year" and to make certain related changes.

     NOW, THEREFORE, the signatory Participants agree as follows:

SECTION 1

AMENDMENT TO RESTATED NEPOOL AGREEMENT


     1.1  AMENDMENT OF SECTION 1.77.  Section 1.77 of the Restated NEPOOL
          Agreement is amended to read as follows:

          POWER YEAR is (i) the period of twelve (12) months commencing on
          November 1, in each year to and including 1997; (ii) the period
          of seven (7) months commencing on November 1, 1998; and (iii) the
          period of twelve (12) months commencing on June 1, 1999 and each
          June 1 thereafter.

     1.2  AMENDMENT OF SECTION 1.104.  Section 1.104 of the Restated NEPOOL
          Agreement is amended to read as follows:

          WINTER PERIOD in each Power Year is (i) the seven-month period
          from November through May and the month of October for the Power
          Year commencing on November 1 in 1997 or a prior Power Year; (ii)
          the seven-month period from November through May for the Power
          Year commencing on November 1, 1998; and (iii) the eight-month
          period from October through May for the Power Year commencing on
          June 1, 1999 and each June 1 thereafter.

     1.3  AMENDMENT OF SECTION 12.2(A)(1), DEFINITION OF "I".  The
          definition of "I" in Section 12.2(a)(1) of the Restated NEPOOL
          Agreement is amended to read as follows:

          I    for the Participant for the month is the percentage which
               represents the weighted average (using the Installed
               Capability of each Installed Capability Entitlement for such
               month for the weighting) of the Four Year Installed
               Capability Target Availability Rates of the Installed
               Capability Entitlements which are included in the
               Participant's Installed System Capability during the hour of
               the coincident peak load of the Participants for the month.
               The Four Year Target Availability Rate for an Installed
               Capability Entitlement for any month is the average of the
               monthly Target Availability Rates for the forty-eight months
               which comprise the period of four consecutive calendar years
               ending within the Power Year which includes such month, as
               determined on the basis of the Target Availability Rates for
               each of the forty-eight months, and as applied on a basis
               which is consistent with the fuel or maturity status of the
               unit for each of the forty-eight months; provided, however,
               that for the purpose of determining the Four Year Target
               Availability Rate (i) for months included within the Power
               Year which commences June 1, 1999, the determination shall
               be made for the months of June through October on the basis
               of the calendar years 1995 through 1998, and shall be made
               for the months of November through May on the basis of the
               calendar years 1996 through 1999, and (ii) for months
               included within the Power Year which commences June 1, 2000,
               the determination shall be made on the basis of the calendar
               years 1996 through 1999.  The Target Availability Rates
               shall be those utilized by the Management Committee in its
               most recent determination of NEPOOL Objective Capability
               pursuant to Section 6.14(e).

     1.4  AMENDMENT OF SECTION 12.2(A)(1), DEFINITION OF "H".  The
          definition of "H" in Section 12.2(a)(1) of the Restated NEPOOL
          Agreement is amended to read as follows:

          H    for the Participant for the month is the percentage which
               represents the weighted average (using the Installed
               Capability of each Installed Capability Entitlement for such
               month for the weighting) of the Four Year Actual
               Availability Rates of the Installed Capability Entitlements
               which are included in the Participant's Installed System
               Capability during the hour of the coincident peak load of
               the Participants for the month.  The Four Year Actual
               Availability Rate for an Installed Capability Entitlement
               for any month is the percentage which represents the average
               of the amounts determined for H{1} for the four applicable
               Twelve-Month Measurement Periods within the forty-eight
               months which comprise the period of four consecutive
               calendar years ending within the Power Year which includes
               such month; provided, however, that for the purpose of
               determining the Four Year Actual Availability Rate (i) for
               months included within the Power Year which commences June
               1, 1999, the determination shall be made for the months of
               June through October on the basis of the calendar years 1995
               through 1998, and shall be made for the months of November
               through May on the basis of the calendar years 1996 through
               1999, and (ii) for months included within the Power Year
               which commences June 1, 2000, the determination shall be
               made on the basis of the calendar years 1996 through 1999.
               A Twelve-Month Measurement Period is a period of twelve
               sequential months.  For purposes of this sequence, the first
               month in the four years and the immediately succeeding
               months shall be considered to follow the forty-eighth month
               in the four-year period.  The four applicable Twelve-Month
               Measurement Periods to be used in the determination of H{1}
               for an Installed Capability Entitlement shall be the four
               sequential Twelve-Month Measurement Periods out of the
               twelve possible combinations which yield the highest H{1}.

     1.5  AMENDMENT OF SECTION 12.2(A)(1), DEFINITION OF "R".  The
          definition of "R" in Section 12.2(a)(1) of the Restated NEPOOL
          Agreement is amended to read as follows:

          R    for the month is the phase-out factor for the month, which
               shall be as follows:

                    R=0.75    for the Power Year beginning November 1,
                              1997.
                    R=0.50    for the 12 month period beginning November 1,
                              1998.
                    R=0.25    for the 12 month period beginning November 1,
                              1999.
                    R=0       for the 12 month period beginning November 1,
                              2000 and all subsequent 12 month periods.


SECTION 2

MISCELLANEOUS

     2.1  Following execution by the requisite number of Participants in
          accordance with the Restated NEPOOL Agreement, this Thirty-
          Seventh Agreement shall become effective November 1, 1998, or on
          such other date or dates as the Commission shall provide that the
          amendments provided for in this Agreement shall become effective;
          provided that such amendments shall not become effective if
          Participants having the requisite number of Voting Shares give
          notice in accordance with Section 21.11 of the Restated NEPOOL
          Agreement that they object to the amendments.

     2.2  Terms used in this Thirty-Seventh Agreement that are not defined
          herein shall have the meanings ascribed to them in the Restated
          NEPOOL Agreement.

     2.3  This Thirty-Seventh Agreement may be executed in any number of
          counterparts and each executed counterpart shall have the same
          force and effect as an original instrument and as if all the
          parties to all the counterparts had signed the same instrument.
          Any signature page of this Thirty-Seventh Agreement may be
          detached from any counterpart of this Thirty-Seventh Agreement
          without impairing the legal effect of any signatures thereof, and
          may be attached to another counterpart of this Thirty-Seventh
          Agreement identical in form thereto but having attached to it one
          or more signature pages.

     IN WITNESS WHEREOF, each of the signatories has caused a counterpart
signature page for this Thirty-Seventh Agreement to be executed by its duly
authorized representative as of August 15, 1998.



<PAGE>

                    COUNTERPART SIGNATURE PAGE
                   TO THIRTY-SEVENTH AGREEMENT
                    AMENDING NEW ENGLAND POWER
                          POOL AGREEMENT



     IN WITNESS WHEREOF, the undersigned has caused this counterpart
signature page to the Thirty-Seventh Agreement Amending New England Power
Pool Agreement, dated as of August 15, 1998, to be executed by its duly
authorized representative as of August 15, 1998.



                              Boston Edison Company________________
                              (Participant)



                              By:/s/ Douglas S. Horan______________
                                 Name: Douglas S. Horan

                                 Title: Senior Vice-President

<PAGE>

                              Central Maine Power Company__________
                              (Participant)



                              By:/s/ Arthur Adelberg______________
                                 Name: Arthur Adelberg

                                 Title: Exec VP

<PAGE>

                              Connecticut Municipal Electric Energy Cooperative
                              (Participant)



                              By:/s/ Maurice R. Scully_____________
                                 Name: Maurice R. Scully

                                 Title: Executive Director

<PAGE>

                              COMMONWEALTH ENERGY SYSTEM COMPANIES_
                              (Participant)
                              Cambridge Electric Light Company
                              Canal Electric Company
                              Commonwealth Electric Company


                              By:/s/ James J. Keane________________
                                 Name: James J. Keane

                                 Title: Vice President
                                        Energy Supply & Engineering Services

<PAGE>

                              EASTERN UTILITIES ASSOCIATES COMPANIES
                              Blackstone Valley Electric Company
                              Eastern Edison Company
                              Newport Electric Company
                              (Participants)


                              By:/s/ Kevin A. Kirby________________
                                 Name: Kevin A. Kirby

                                 Title: Vice President

<PAGE>

                              Fitchburg Gas and Electric Light Company
                              (Participant)



                              By:/s/ David K. Foote________________
                                 Name: David K. Foote

                                 Title: Senior Vice President

<PAGE>

                              Hingham Municipal Lighting Plant_____
                              (Participant)



                              By:/s/ Joseph K. Spadea, Jr._________
                                 Name: Joseph K. Spadea, Jr.

                                 Title: G.M.

<PAGE>

                              Granite State Electric Company_______
                              (Participant)



                              By:/s/ John G. Cochrane______________
                                 Name: John G. Cochrane

                                 Title: Assistant Treasurer

<PAGE>

                              Massachusetts Electric Company_______
                              (Participant)



                              By:/s/ John G. Cochrane______________
                                 Name: John G. Cochrane

                                 Title: Treasurer

<PAGE>

                              The Narragansett Electric Company____
                              (Participant)



                              By:/s/ John G. Cochrane______________
                                 Name: John G. Cochrane

                                 Title: Treasurer

<PAGE>

                              New England Power Company____________
                              (Participant)



                              By:/s/ Cheryl A. Lafleur_____________
                                 Name: Cheryl A. Lafleur

                                 Title: Vice President

<PAGE>

                              North American Energy Conservation, Inc.
                              (Participant)



                              By:/s/ William J. Wagers_____________
                                 Name: William J. Wagers

                                 Title: Director, Electric
                                        Wholesale Marketing

<PAGE>

                              NORTHEAST UTILITIES SYSTEM COMPANIES_
                              The Connecticut Light and Power Company
                              Holyoke Power and Electric Company
                              Holyoke Water Power Company
                              Public Service Company of New Hampshire
                              Western Massachusetts Electric Company
                              (Participants)



                              By:/s/ Frank P. Sabatino_____________
                                 Name: Frank P. Sabatino

                                 Title: Vice President of Wholesale Marketing

<PAGE>

                              SOUTH HADLEY ELECTRIC LIGHT DEPARTMENT
                              (Participant)



                              By:/s/ Wayne D. Doerpholz____________
                                 Name: Wayne D. Doerpholz

                                 Title: Manager

<PAGE>

                              PG&E Energy Trading-Power, L.P.______
                              (Participant)



                              By:/s/ Sarah M. Barpoulis____________
                                 Name: Sarah M. Barpoulis

                                 Title: Senior Vice President

<PAGE>

                              Strategic Energy Ltd.________________
                              (Participant)



                              By:/s/ John E. Molinda_______________
                                 Name: John E. Molinda

                                 Title: Director, Electricity Market &
                                        Strategy Development

<PAGE>

                              The United Illuminating Company______
                              (Participant)



                              By:/s/ Stephen Goldschmidt___________
                                 Name: Stephen Goldschmidt

                                 Title: VP Planning & Information Resources

<PAGE>

                              Unitil Resources, Inc._______________
                              (Participant)



                              By:/s/ James G. Daly_________________
                                 Name: James G. Daly

                                 Title: President

<PAGE>

                              Unitil Power Corp.___________________
                              (Participant)



                              By:/s/ David K. Foote________________
                                 Name: David K. Foote

                                 Title: Senior Vice President

<PAGE>

                              Velco________________________________
                              (Participant)



                              By:/s/ Richard M. Chapman____________
                                 Name: Richard M. Chapman

                                 Title: President and CEO
                                        Pres/CEO

<PAGE>

                              _____________________________________
                              (Participant)



                              By:__________________________________
                                 Name:

                                 Title: