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                                                          Exhibit 4.2

                         SECOND AMENDMENT TO RIGHTS AGREEMENT

1.  GENERAL BACKGROUND. In accordance with Section 27, Supplements and
    Amendments, of the Rights Agreement dated April 20, 2000 between Fleet
    National Bank and Pennichuck Corporation ("Pennichuck"), as amended by
    Amendment to Rights Agreement dated as of October 10, 2001 (the
    "Agreement"), Pennichuck and EquiServe Trust Company, N.A., as successor
    rights agent under the Agreement (the "Rights Agent"), desire to further
    amend the Agreement as set forth herein.

2.  EFFECTIVENESS. This Second Amendment shall be effective as of January 14,
    2002 (the "Second Amendment") and all defined terms and definitions in
    the Agreement shall be the same in this Second Amendment except as
    specifically revised by this Second Amendment.

3.  REVISION. Section 21 of the Agreement entitled "Change of Rights Agent"
    is hereby deleted in its entirety and replaced with the following:

    Section 21. CHANGE OF RIGHTS AGENT. The Rights Agent or any successor
    Rights Agent may resign and be discharged from its duties under this
    Agreement upon 30 days' notice in writing mailed to the Company and to each
    transfer agent of the Common Shares and the Preferred Shares by registered
    or certified mail, and to the holders of the Right Certificates by
    first-class mail. The Company may remove the Rights Agent or any successor
    Rights Agent upon 30 days' notice in writing, mailed to the Rights Agent or
    successor Rights Agent, as the case may be, and to each transfer agent of
    the Common Shares and the Preferred Shares by registered or certified mail,
    and to the holders of the Right Certificates by first-class mail. If the
    Rights Agent shall resign or be removed or shall otherwise become incapable
    of acting, the Company shall appoint a successor to the Rights Agent. If the
    Company shall fail to make such appointment within a period of 30 days after
    giving notice of such removal or after it has been notified in writing of
    such resignation or incapacity by the resigning or incapacitated Rights
    Agent or by the holder of a Right Certificate (who shall, with such notice,
    submit his Right Certificate for inspection by the Company), then the
    registered holder of any Right Certificate may apply to any court of
    competent jurisdiction for the appointment of a new Rights Agent. Any
    successor Rights Agent, whether appointed by the Company or by such a court,
    shall be a corporation or trust company organized and doing business under
    the laws of the United States or of any state of the United States, in good
    standing, which is authorized under such laws to exercise corporate trust

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    or stock transfer powers and is subject to supervision or examination by
    federal or state authority and which has individually or combined with an
    affiliate at the time of its appointment as Rights Agent a combined capital
    and surplus of at least $10 million dollars. After appointment, the
    successor Rights Agent shall be vested with the same powers, rights,
    duties and responsibilities as if it had been originally named as Rights
    Agent without further act or deed; but the predecessor Rights Agent shall
    deliver and transfer to the successor Rights Agent any property at the
    time held by it hereunder, and execute and deliver any further assurance,
    conveyance, act or deed necessary for the purpose. Not later than the
    effective date of any such appointment the Company shall file notice
    thereof in writing with the predecessor Rights Agent and each transfer
    agent of the Common Shares and the Preferred Shares, and mail a notice
    thereof in writing to the registered holders of the Right Certificates.
    Failure to give any notice provided for in this Section 21, however, or
    any defect therein, shall not affect the legality or validity of the
    resignation or removal of the Rights Agent or the appointment of the
    successor Rights Agent, as the case may be.

4.  Except as amended hereby, the Agreement and all schedules or exhibits
    thereto shall remain in full force and effect.

    IN WITNESS WHEREOF, the parties hereto have caused this Second Amendment
to be executed in their names and on their behalf by and through their duly
authorized officers, as of the 14th day of January, 2002.

PENNICHUCK CORPORATION                  EQUISERVE TRUST COMPANY, N.A.

/s/ Charles J. Staab                    /s/ Carol Mulvey-Eori
---------------------------------       ----------------------------------
By: Charles J. Staab                    By: Carol Mulvey-Eori
Title: Vice President, Treasurer        Title: Managing Director,
       and Chief Financial Officer             Client Administration<PAGE>

                                                                     Exhibit 4.3

                   AGREEMENT OF SUBSTITUTION AND AMENDMENT OF
                         COMMON SHARES RIGHTS AGREEMENT

         This Agreement of Substitution and Amendment is entered into as of
January 15, 2002, by and between Pennichuck Corporation, a New Hampshire
corporation (the "Company") and American Stock Transfer and Trust Company, a New
York banking corporation ("AST").

                                    RECITALS

A.       On or about April 20, 2000, the Company entered into a Rights
         Agreement, as subsequently amended (the "Rights Agreement") with Fleet
         National Bank as rights agent.

B.       On or about October 10, 2001, EquiServe Trust Company, N.A., an
         affiliate of Fleet National Bank, was appointed as successor rights
         agent under the Rights Agreement (the "Predecessor Agent").

C.       The Company wishes to remove the Predecessor Agent and substitute AST
         as rights agent pursuant to Section 21 of the Rights Agreement.

D.       The Company has given the Predecessor Agent proper notice of removal
         of the Predecessor Agent as rights agent.

                                   AGREEMENT

         NOW THEREFORE, in consideration of the foregoing and of other
consideration, the sufficiency of which is hereby acknowledged, the parties
agree as follows:

1.       The Company hereby appoints AST as rights agent pursuant to Section 21
         of the Rights Agreement, to serve in that capacity for the
         consideration and subject to all of the terms and conditions of the
         Rights Agreement.

2.       AST hereby accepts the appointment as rights agent pursuant to Section
         21 of the Rights Agreement and agrees to serve in that capacity for the
         consideration and subject to all of the terms and conditions of the
         Rights Agreement.

3.       From and after the effective date hereof, each and every reference in
         the Rights Agreement to a "Rights Agent" shall be deemed to be a
         reference to AST.

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                                      -2-

4.       Section 3(c) of the Rights Agreement is amended by striking the form of
         the legend contained in said section and substituting the following in
         lieu thereof:

                  This certificate also evidences and entitles the holder hereof
                  to certain Rights as set forth in a Rights Agreement between
                  Pennichuck Corporation and American Stock Transfer & Trust
                  Company as Rights Agent, dated as of April 20, 2000, as
                  amended (the "Rights Agreement"), the terms of which are
                  hereby incorporated herein by reference and a copy of which is
                  on file at the principal executive offices of Pennichuck
                  Corporation. Under certain circumstances, as set forth in the
                  Rights Agreement, such Rights will be evidenced by separate
                  certificates and will no longer be evidenced by this
                  certificate. Pennichuck Corporation will mail to the holder of
                  this certificate a copy of the Rights Agreement without charge
                  after a receipt of a written request therefor. Under certain
                  circumstances, Rights that are or were acquired or
                  beneficially owned by Acquiring Persons (as defined in the
                  Rights Agreement) may become null and void.

5.       Section 26 of the Rights Agreement is amended to provide that notices
         or demands shall be addressed as follows (until another address is
         filed):

         If to the Company:             Pennichuck Corporation
                                        4 Water Street, P.O. Box 448
                                        Nashua, New Hampshire 03061-0448
                                        Attention: President

         with a copy to:                Gallagher, Callahan & Gartrell, P.A.
                                        214 North Main Street, P.O. Box 1415
                                        Concord, New Hampshire 03302-1415

         If to AST:                     American Stock Transfer & Trust Company
                                        59 Maiden Lane
                                        New York, NY 10038
                                        Attention: Shareholder Services Division

6.       Except as expressly modified herein, the Rights Agreement shall remain
         in full force and effect.

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                                      -3-

7.       This Agreement of Substitution and Amendment may be executed in one or
         more counterparts, each of which shall together constitute one and the
         same document.

         IN WITNESS WHEREOF, the parties have caused this Agreement to be duly
executed as of the date indicated above.

                                        PENNICHUCK CORPORATION

                                        By: /s/ Charles J. Staab
                                            -----------------------------------
                                            Charles J. Staab
                                            Vice President, Treasurer and
                                            Chief Financial Officer

                                        AMERICAN STOCK TRANSFER & TRUST COMPANY

                                        By: /s/ Herbert J. Lemmer
                                            -----------------------------------
                                            Herbert J. Lemmer
                                            Vice President

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