EXHIBIT 99.3
 
[PROXY CARD]
 
                             COLONIAL GAS COMPANY
                   THIS PROXY IS SOLICITED ON BEHALF OF THE
              DIRECTORS FOR THE FEBRUARY  , 1999 SPECIAL MEETING
 
  The undersigned stockholder of Colonial Gas Company (the "Company") hereby
appoints Carol E. Elden and Dennis W. Carroll (each with power to act without
the other and with power of substitution) proxies to represent the undersigned
at the special meeting of Stockholders of the Company to be held on    ,
February  , 1999 at 11:00 a.m. Eastern Standard Time, at BankBoston, 100
Federal Street, Boston Massachusetts, and at any adjournment thereof, with all
the power the undersigned would possess if personally present, and to vote, as
designated below, all shares of Common Stock of the company which the
undersigned may be entitled to vote at said Meeting, hereby revoking any proxy
heretofore given. IN THEIR DISCRETION, THE PROXIES ARE AUTHORIZED TO VOTE UPON
SUCH OTHER BUSINESS AS MAY PROPERLY COME BEFORE THE MEETING.
 
  The matters referred to on the reverse side are more fully described in the
Notice of and Joint Proxy Statement/Prospectus for the Special Meeting,
receipt of which is hereby acknowledged. THE DIRECTORS UNANIMOUSLY RECOMMEND
THAT STOCKHOLDERS VOTE FOR THE APPROVAL OF THE PROPOSED MERGER AGREEMENT WITH
EASTERN ENTERPRISES. The Shares represented by this proxy will be voted in
accordance with the specification made on the reverse side. If no
specification is made, the proxy will be voted in accordance with the
Directors' recommendations.
 
              [IMPORTANT--TO BE SIGNED AND DATED ON REVERSE SIDE]

 
                        [FORM OF REVERSE OF PROXY CARD]
 
The Board of Directors recommends a vote FOR approval of the Agreement and Plan
of Reorganization, dated as of October 17, 1998, between Colonial Gas Company
and Eastern Enterprises (the "Merger Agreement").
 

                                                                    
                                          FOR       AGAINST       ABSTAIN
1.Approval of Merger Agreement.           [_]         [_]           [_]

 
2.    To transact such other business as may properly come before the meeting
      or any adjournment thereof.
 
MARK HERE                                     MARK HERE
FOR ADDRESS                                   IF YOU PLAN
CHANGE AND                                    TO ATTEND
NOTE AT LEFT [_]                              THE MEETING [_]
 
NOTE: Please sign name exactly as your name(s) appears. If shares are held
jointly, both holders should sign. When signing as attorney, executor,
administrator, trustee or guardian, please give full title as such. If a
corporation, please sign in full corporate name by president or other
authorized officer. If a partnership, please sign in partnership name by
authorized person.
 
Signature ___________________________   Date ________________________________
 
Signature ___________________________   Date ________________________________