Exhibit 10.35

        AMENDED AND RESTATED MASTER GUARANTEE REIMBURSEMENT
                               AND LOAN AGREEMENT


      This AGREEMENT is entered into as of the 26th day of February, 1998 by and
among Thermo Electron  Corporation  (the "Parent") and those of its subsidiaries
that  join in this  Agreement  by  executing  the  signature  page  hereto  (the
"Majority Owned Subsidiaries").

                                   WITNESSETH:

      WHEREAS,   the  majority  owned   subsidiaries   and  their   wholly-owned
subsidiaries  wish  to  enter  into  various  financial  transactions,  such  as
convertible or  nonconvertible  debt,  loans,  and equity  offerings,  and other
contractual  arrangements with third parties (the "Underlying  Obligations") and
may  provide  credit  support  to,  on behalf of or for the  benefit  of,  other
subsidiaries of the Parent ("Credit Support Obligations");

      WHEREAS,  the Majority Owned  Subsidiaries and the Parent acknowledge that
the Majority  Owned  Subsidiaries  and their  wholly-owned  subsidiaries  may be
unable to enter into many kinds of Underlying Obligations without a guarantee of
their performance  thereunder from the Parent (a "Parent  Guarantee") or without
obtaining Credit Support Obligations from other Majority Owned Subsidiaries;

      WHEREAS,   the  Majority  Owned   Subsidiaries   and  their   wholly-owned
subsidiaries may borrow funds from the Parent,  and the Parent may loan funds or
provide  credit  to the  Majority  Owned  Subsidiaries  and  their  wholly-owned
subsidiaries, on a short-term and unsecured basis;

      WHEREAS, certain Majority Owned Subsidiaries ("Second Tier
Majority Owned Subsidiaries ") may themselves be majority owned
subsidiaries of other Majority Owned Subsidiaries ("First Tier
Majority Owned Subsidiaries");

      WHEREAS, for various reasons,  Parent Guarantees of a Second Tier Majority
Owned Subsidiary's  Underlying Obligations may be demanded and given without the
respective First Tier Majority Owned Subsidiary also issuing a guarantee of such
Underlying
Obligation;

      WHEREAS,  the Parent may itself make a loan or provide  other  credit to a
Second Tier Majority Owned  Subsidiary or its  wholly-owned  subsidiaries  under
circumstances where the applicable First Tier Majority Owned Subsidiary does not
provide such credit; and

      WHEREAS,  the Parent is willing to  consider  continuing  to issue  Parent
Guarantees and providing credit, and the Majority Owned Subsidiaries are willing
to consider  continuing  to provide  Credit  Support  Obligations  and to borrow
funds, on the terms and conditions set forth below;

      NOW,  THEREFORE,  in  consideration  of the  foregoing  and other good and
valuable  consideration,  the  receipt  and  sufficiency  of  which  are  hereby
acknowledged by each party hereto, the parties agree as follows:

1.     If the Parent provides a Parent Guarantee of an Underlying
      Obligation, and the beneficiary(ies) of the Parent Guarantee
      enforce the Parent Guarantee, or the Parent performs under
      the Parent Guarantee for any other reason, then the Majority
      Owned Subsidiary that is obligated, either directly or
      indirectly through a wholly-owned subsidiary, under such
      Underlying Obligation shall indemnify and save harmless the
      Parent from any liability, cost, expense or damage
      (including reasonable attorneys' fees) suffered by the
      Parent as a result of the Parent Guarantee.  If the
      Underlying Obligation is issued by a Second Tier Majority
      Owned Subsidiary or a wholly-owned subsidiary thereof, and
      such Second Tier Majority Owned Subsidiary is unable to
      fully indemnify the Parent (because of the poor financial
      condition of such Second Tier Majority Owned Subsidiary, or
      for any other reason), then the First Tier Majority Owned
      Subsidiary that owns the majority of the stock of such
      Second Tier Majority Owned Subsidiary shall indemnify and
      save harmless the Parent from any remaining liability, cost,
      expense or damage (including reasonable attorneys' fees)
      suffered by the Parent as a result of the Parent Guarantee.
      If a Majority Owned Subsidiary or a wholly-owned subsidiary
      thereof provides a Credit Support Obligation for any
      subsidiary of the Parent, other than a subsidiary of such
      Majority Owned Subsidiary, and the beneficiary(ies) of the
      Credit Support Obligation enforce the Credit Support
      Obligation, or the Majority Owned Subsidiary or its
      wholly-owned subsidiary  performs under the Credit Support
      Obligation for any other reason, then the Parent shall
      indemnify and save harmless the Majority Owned Subsidiary or
      its wholly-owned subsidiary, as applicable, from any
      liability, cost, expense or damage (including reasonable
      attorneys' fees) suffered by the Majority Owned Subsidiary
      or its wholly-owned subsidiary, as applicable, as a result
      of the Credit Support Obligation.  Without limiting the
      foregoing, Credit Support Obligations include the deposit of
      funds by a Majority Owned Subsidiary or a wholly-owned
      subsidiary thereof in a credit arrangement with a banking
      facility whereby such funds are available to the banking
      facility as collateral for overdraft obligations of other
      Majority Owned Subsidiaries or their subsidiaries also
      participating in the credit arrangement with such banking
      facility.

2.     For purposes of this Agreement, the term "guarantee" shall
      include not only a formal guarantee of an obligation, but
      also any other arrangement where the Parent is liable for
      the obligations of a Majority Owned Subsidiary or its
      wholly-owned subsidiaries.  Such other arrangements include
      (a) representations, warranties and/or covenants or other
      obligations joined in by the Parent, whether on a joint or
      joint and several basis, for the benefit of the Majority
      Owned Subsidiary or its wholly-owned subsidiaries and (b)
      responsibility of the Parent by operation of law for the
      acts and omissions of the Majority Owned Subsidiary or its
      wholly-owned subsidiaries, including controlling person
      liability under securities and other laws.

3.    Promptly after the Parent receives notice that a beneficiary
      of a Parent Guarantee is seeking to enforce such Parent
      Guarantee, the Parent shall notify the Majority Owned
      Subsidiary(s) obligated, either directly or indirectly
      through a wholly-owned subsidiary, under the relevant
      Underlying Obligation.  Such Majority Owned Subsidiary(s) or
      wholly-owned subsidiary thereof, as applicable, shall have
      the right, at its own expense, to contest the claim of such
      beneficiary.  If a Majority Owned Subsidiary or wholly-owned
      subsidiary thereof, as applicable, is contesting the claim
      of such beneficiary, the Parent will not perform under the
      relevant Parent Guarantee unless and until, in the Parent's
      reasonable judgment, the Parent is obligated under the terms
      of such Parent Guarantee to perform.  Subject to the
      foregoing, any dispute between a Majority Owned Subsidiary
      or wholly-owned subsidiary thereof, as applicable, and a
      beneficiary of a Parent Guarantee shall not affect such
      Majority Owned Subsidiary's obligation to promptly indemnify
      the Parent hereunder.  Promptly after a Majority Owned
      Subsidiary or wholly-owned subsidiary thereof, as
      applicable, receives notice that a beneficiary of a Credit
      Support Obligation is seeking to enforce such Credit Support
      Obligation, the Majority Owned Subsidiary shall notify the
      Parent.  The Parent shall have the right, at its own
      expense, to contest the claim of such beneficiary.  If the
      Parent or the subsidiary of the Parent on whose behalf the
      Credit Support Obligation is given is contesting the claim
      of such beneficiary, the Majority Owned Subsidiary or
      wholly-owned subsidiary thereof, as applicable, will not
      perform under the relevant Credit Support Obligation unless
      and until, in the Majority Owned Subsidiary's reasonable
      judgment, the Majority Owned Subsidiary or wholly-owned
      subsidiary thereof, as applicable, is obligated under the
      terms of such Credit Support Obligation to perform.  Subject
      to the foregoing, any dispute between the Parent or the
      subsidiary of the Parent on whose behalf the Credit Support
      Obligation was given, on the one hand, and a beneficiary of
      a Credit Support Obligation, on the other, shall not affect
      the Parent's obligation to promptly indemnify the Majority
      Owned Subsidiary or its wholly-owned subsidiary, as
      applicable, hereunder.

4.    Upon the request of a Majority Owned Subsidiary, the Parent
      may make loans and advances to the Majority Owned Subsidiary
      or its wholly-owned subsidiaries on a short-term, revolving
      credit basis, from time to time in such amounts as mutually
      determined by the Parent and the Majority Owned Subsidiary.
      The aggregate principal amount of such loans and advances
      shall be reflected on the books and records of the Majority
      Owned Subsidiary (or wholly-owned subsidiary, as applicable)
      and the Parent.  All such loans and advances shall be on an
      unsecured basis unless specifically provided otherwise in
      loan documents executed at that time.  The Majority Owned
      Subsidiary or its wholly-owned subsidiaries, as applicable,
      shall pay interest on the aggregate unpaid principal amount
      of such loans from time to time outstanding at a rate
      ("Interest Rate") equal to the rate of the Commercial Paper
      Composite Rate for 90-day maturities as reported by Merrill
      Lynch Capital Markets, as an average of the last five
      business days of such Majority Owned Subsidiary's latest
      fiscal quarter then ended, plus twenty-five (25) basis
      points.  The Interest Rate shall be adjusted on the first
      business day of each fiscal quarter of such Majority Owned
      Subsidiary pursuant to the Interest Rate formula contained
      in the preceding sentence and shall be in effect for the
      entirety of such fiscal quarter.  Interest shall be computed
      on a 360-day basis.  The aggregate principal amount
      outstanding and accrued interest thereon shall be payable on
      demand.  The principal and accrued interest may be paid by
      the Majority Owned Subsidiaries or their wholly-owned
      subsidiaries, as applicable, at any time or from time to
      time, in whole or in part, without premium or penalty.  All
      payments shall be applied first to accrued interest and then
      to principal.  Principal and interest shall be payable in
      lawful money of the United States of America, in immediately
      available funds, at the principal office of the Parent or at
      such other place as the Parent may designate from time to
      time in writing to the Majority Owned Subsidiary.  The
      unpaid principal amount of any such borrowings, and accrued
      interest thereon, shall become immediately due and payable,
      without demand, upon the failure of the Majority Owned
      Subsidiary or its wholly-owned subsidiary, as applicable, to
      pay its debts as they become due, the insolvency of the
      Majority Owned Subsidiary or its wholly-owned subsidiary, as
      applicable, the filing by or against the Majority Owned
      Subsidiary or its wholly-owned subsidiary, as applicable, of
      any petition under the U.S. Bankruptcy Code (or the filing
      of any similar petition under the insolvency law of any
      jurisdiction), or the making by the Majority Owned
      Subsidiary or its wholly-owned subsidiary, as applicable, of
      an assignment or trust mortgage for the benefit of creditors
      or the appointment of a receiver, custodian or similar agent
      with respect to, or the taking by any such person of
      possession of, any property of the Majority Owned Subsidiary
      or its wholly-owned subsidiary, as applicable.  In case any
      payments of principal and interest shall not be paid when
      due, the Majority Owned Subsidiary or its wholly-owned
      subsidiary, as applicable, further promises to pay all cost
      of collection, including reasonable attorneys' fees.

5.    If the Parent makes a loan or provides other credit ("Credit
      Extension") to a Second Tier Majority Owned Subsidiary, the
      First Tier Majority Owned Subsidiary that owns the majority
      of the stock of such Second Tier Majority Owned Subsidiary
      hereby guarantees the Second Tier Majority Owned
      Subsidiary's obligations to the Parent thereunder.  Such
      guaranty shall be enforced only after the Parent, in its
      reasonable judgment, determines that the Second Tier
      Majority Owned Subsidiary is unable to fully perform its
      obligations under the Credit Extension.  If the Parent
      provides Credit Extension to a wholly-owned subsidiary of a
      Second Tier Majority Owned Subsidiary, the Second Tier
      Majority Owned Subsidiary hereby guarantees it wholly-owned
      subsidiary's obligations to the Parent thereunder and the
      First Tier Majority Owned Subsidiary that owns the majority
      of the stock of such Second Tier Majority Owned Subsidiary
      hereby guarantees the Second Tier Majority Owned
      Subsidiary's obligations to the Parent hereunder.  Such
      guaranty by the First Tier Majority Owned Subsidiary shall
      be enforced only after the Parent, in its reasonable
      judgment, determines that the Second Tier Majority Owned
      Subsidiary is unable to fully perform its guaranty
      obligation hereunder.

6.    All payments  required to be made by a Majority  Owned  Subsidiary  or its
      wholly-owned  subsidiaries,  as applicable,  shall be made within two days
      after receipt of notice from the Parent.  All payments required to be made
      by the Parent  shall be made within two days after  receipt of notice from
      the Majority Owned Subsidiary.

7.    This Agreement  shall be governed by and construed in accordance  with the
      laws of the Commonwealth of Massachusetts applicable to contracts made and
      performed therein.







      IN WITNESS WHEREOF,  the parties have caused this Agreement to be executed
by their duly authorized officers as of the date first above written.


      THERMO ELECTRON CORPORATION


                               By:  /s/ Melissa F. Riordan
                                    Melissa F. Riordan
                               Title:     Treasurer


                               THERMO TERRATECH INC.


                               By:  /s/ John P. Appleton
                                    John P. Appleton
                               Title:     President