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                                                                    EXHIBIT 10.6

                              SECOND AMENDMENT TO
                  BENTHOS, INC. EMPLOYEE STOCK OWNERSHIP PLAN
            as Amended and Restated Effective as of October 1, 1987


          AMENDMENT adopted this 22/nd/ day of October 1997, by Benthos, Inc.
(hereinafter referred to as the "Company"):


                                  WITNESSETH:
                                  ----------

          WHEREAS, the Company has heretofore adopted a defined contribution
plan known as the "Benthos, Inc. Employee Stock Ownership Plan", which was
amended and restated effective as of July 1, 1987 (the "Plan") and

          WHEREAS the Company previously amended said amended and restated Plan
to make a technical modification to the provisions pertaining to the limit on
"annual additions;" and

          WHEREAS, the Company, pursuant to Section 16.1 of the Plan, has
reserved the right to amend the Plan at any time by vote of its Board of
Directors; and

          WHEREAS, the Company wishes to amend further the Plan to permit
distributions to Participants or their Beneficiaries as soon as practicable
following retirement, death or other termination of employment.

          NOW, THEREFORE, effective as of October 1, 1996, unless otherwise
specified, the Plan is hereby amended as follows:

          1. Section 8.1(a) is amended to read as follows:

                    (a) Upon a Participant's attaining his Normal Retirement
               Age, or upon his becoming a Disabled Participant, he shall become
               entitled to the total value of his Account. The amount to which
               the Participant is entitled shall be paid as provided in this
               Article VIII in the form specified in Section 8.2 as soon as
               practicable following his Normal Retirement Date, or if later,
               his actual retirement date, but in no event shall commence later
               than the earlier of (i) 60 days after the end of the Plan Year in
               which he retires, unless the Participant elects to defer the
               payment of his benefit pursuant to subsection (b) or (ii) his
               Required Distribution Date. Any additional amounts to which a
               retired or Disabled Participant who has received a distribution
               shall become entitled (for example, as a result of an additional
               Company contribution or allocation or forfeiture) shall be paid
               to him as soon as practicable following the end of the Plan Year
               in which such distribution was made.

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     2. The reference in Section 9.3(a) to "Section 12.7" is hereby changed to
     "Section 12.5."

     3. The first sentence of Section 9.3(c) is amended to read as follows:

                 The amount to which the Beneficiary is entitled shall be
            available for distribution to the Beneficiary as soon as practicable
            following the death of the Participant.

     4. Section 10.2(a) is deleted in its entirety and the following
     substituted therefor:

                 (a)  If the vested value of the Account of an Inactive
            Participant whose employment terminated before attaining Normal
            Retirement Age does not exceed $3,500 ($5,000 for Plan Years
            beginning on or after October 1, 1997), the Administrative Committee
            shall direct the Trustee to distribute the vested value to such
            Participant in a lump sum in whole Shares with fractional Shares
            paid in cash without the consent of the Participant. Subject to the
            requirements of Section 12.5, this distribution shall be made as
            soon as practicable following the termination of the Inactive
            Participant's employment. If the vested value of the Account of an
            Inactive Participant whose employment terminated before attaining
            his Normal Retirement Age exceeds $3,500 ($5,000 for Plan Years
            beginning on or after October 1, 1997) the individual may elect to
            have the vested value paid to him or applied for his benefit in
            accordance with the provisions of Article VIII as soon as
            practicable following his termination of employment or at any time
            thereafter. The vested value of an Inactive Participant's Account
            shall be determined as of the Valuation Date immediately preceding
            or coinciding with his Benefit Starting Date.

     In all other respects of the terms of the Plan remain unchanged and in full
force and effect.

     IN WITNESS WHEREOF, the undersigned Company has caused this Amendment to be
executed by its duly authorized officer as of the day and year set forth above.

                                        BENTHOS, INC.

                                        By: /s/ JOHN L. COUGHLIN
                                            ----------------------------
                                            John L. Coughlin

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