William G. Sudhaus
Senior Vice President                                              Exhibit 10.27

                 [LETTERHEAD OF CORESTATES BANK APPEARS HERE]

June 3, 1997



Mr. Stanley D. Piekos
Chief Financial Officer
Brooks Automation, Inc.
15 Elizabeth Drive
Chelmsford, Ma. 08124

Dear Stan:

This letter serves to amend and replace the letter agreement dated June 18, 1996
which established a $3,000,000 discretionary line of credit for foreign currency
borrowing. The amount is now being increased to $6,000,000. In addition this 
letter will serve to amend the date in paragraph 1 (b) Requests for Loans, in 
                                                       ------------------
the Master Short Term Foreign Currency Borrowing Agreement from December 31, 
1997 to December 31, 1998, (a copy of which is attached). All other terms and 
conditions remain the same.

BORROWER(S):                 Brooks Automation Inc.
                             Brooks Automation Canada Corp.
                             Brooks Automation K.K.
                             Brooks automation Ltd.
                             Brooks Automation Massachusetts Securities Corp.

LENDER:                      CoreStates Bank N.A.

LOAN TYPE AND AMOUNT:        $6,000,000 Unsecured Discretionary Line of Credit

AVAILABILITY:                The maximum outstanding under this facility at any 
                             one time shall be the equivalent of $6,000,000 USD
                             in any other currency mutually agreed between the
                             Borrowers and the Bank.

PURPOSE:                     Working capital and other short term corporate 
                             purposes.

COLLATERAL:                  None

INTEREST RATE:               LIBOR plus 200 b.p. for maturities of 30,60,90 or 
                             180 days.

INTEREST PAYMENTS:           In case of 30, 60 or 90-day loans, at maturity. In 
                             the case of 180-day loans, at the end of 90 days
                             and at maturity.





 
Mr. Stanley D. Piekos, Chief Financial Officer
June 3, 1997
Page Two


MINIMUM LOANS:          $250,000 US dollar equivalent.

PREPAYMENTS
PROHIBITIONS:           LIBOR loans may not be prepaid prior to maturity without
                        a potential breakage fee depending upon the interest
                        rate market at the time of prepayment.

REPORTING 
REQUIREMENTS:           1.    Quarterly, within 45 days after the end of each of
                              the first three fiscal quarters.

                              a.    Consolidated financial statements prepared
                                    by the Company.

                              b.    Certificate of covenant compliance with all
                                    Bank debt.

                        2.    Within 90 days after the end of each fiscal year.
   
                              a.    Consolidated financial statements prepared
                                    and certified by an independent certified
                                    public accountant.

                              b.    Certificate of covenant compliance.

                              c.    Principal financial officer and accountant's
                                    statement of no default.

                        3.    Promptly after the filing of the same, copies of
                              all reports, proxy statements and financial
                              statements that the Borrower files with the U.S.
                              Securities and Exchange Commission or any
                              comparable department in a foreign country.

OTHER CONDITIONS TO
THE LINE OF CREDIT:     1.    Master Short Term Borrowing Agreement, Corporate 
                              Borrowing Resolution and Negative Pledge Agreement
                              (previously dated 6/18/96 and executed 6/25/96).




 
Mr. Stanley D. Piekos, Chief Financial Officer
June 3, 1997
Page Three


If the foregoing is satisfactory, please sign this letter and return to my 
attention.


Very truly yours,

/s/ R. Thomas Esser

R. Thomas Esser
Vice President

RTE/vb



AGREED AND ACCEPTED:


/s/ Stanley D. Piekos                                 August 12, 1997
- ---------------------------------                 -----------------------------
Name and Title                                    Date

Stanley D. Piekos
Vice President & CFO

 
            MASTER SHORT TERM FOREIGN CURRENCY BORROWING AGREEMENT
            ------------------------------------------------------

June 18, 1996                             [LOGO OF CORESTATES BANK APPEARS HERE]

Brooks Automation, Inc.
Brooks Automation Canada Corp.
Brooks Automation K.K.
Brooks Automation Ltd.
Brooks Automation Massachusetts Securities Corp.
15 Elizabeth Drive
Chelmsford, MA 01824

Dear Sirs:

        The purpose of this Agreement is to supplement the letter agreement 
dated June 18, 1996 ("Letter Agreement") between us, CoreStates Bank N.A. 
("Bank") and you, each of the addressees of this Agreement ("Borrower(s)") to 
further describe how the foreign currency loans will be made pursuant to the 
foreign currency line of credit described in the Letter Agreement ("Loan(s)"). 
The Letter Agreement is attached hereto and incorporated by reference herein. 
This Agreement does not constitute a commitment to lend or to make advances. It 
is understood and agreed that any and all Loans will be governed by the 
following:

        1.  Requests for Loans.  From time to time, before the earlier to occur
            ------------------
of (a) a Default under Section 10 hereof, or (b) December 31, 1997, your duly 
authorized officer or other duly authorized person may request Loans by 
telephone or by letter. If we agree to make a Loan, then we will credit the 
proceeds to your designated account with us. Upon your request we will forward 
to you at your address set forth in Paragraph 15 written advices or statements 
of Loans, which will specify rate or rates of interest payable on the Loans, and
such other terms as may have been agreed to.

        2.  Resolutions Authorizing Loans.  Any and all documents required to be
            -----------------------------
executed in connection with Loans may be signed by any of the officers or other 
persons duly authorized by your borrowing resolutions as in effect from time to 
time, provided that a copy of such resolutions is certified by the Secretary or 
an Assistant Secretary of your corporation and delivered to us. We shall incur 
no liability to you or any other person in acting on any request for a Loan 
which we believe in good faith to have been made by a person duly authorized to 
borrow on your behalf as set forth in your borrowing resolutions.



 
        3.  Bank Records Conclusive.  The terms of each Loan including the rate 
            -----------------------
of interest thereon and your payments of principal and interest, as well as any 
special terms and details of each such Loan, shall be established and evidenced 
by this Agreement, the Letter Agreement and by our records, which shall be 
conclusively deemed to be correct in the absence of manifest error.

        4.  Payment of Loans.  All Loans shall be payable on demand, time or 
            ----------------
other basis mutually agreed upon at the time the Loan is made. Loans which are 
payable on a basis other than demand are subject to the prepayment penalties 
described in the Letter Agreement and may not be prepaid prior to their maturity
date or dates without payment of such penalties, if any. Upon the payment in 
whole or in part of any Loan as provided above, accrued and unpaid interest on 
the amount repaid shall be simultaneously paid.

        5.  Interest.  (a) Interest on each Loan shall be computed at the 
            --------
applicable LIBOR rate plus 200 basis points and, with resect to 30, 60, or 90 
day, Loans shall be payable upon maturity and, with respect to 180 day Loans, 
shall be payable at 90 days and at maturity. The term LIBOR rate shall mean and 
refer to LIBOR rate applicable at that time in the country of the foreign 
currency which is borrowed.

        (b)  Each overdue payment of principal on any Loan and, to the extent 
permitted by law, each overdue payment of interest shall bear interest, payable 
on demand, for each day until paid at a rate per annum equal to 2% in excess of
the current interest rate applicable to that Loan.

        (c)  Unless otherwise agreed, interest on all Loans shall be computed on
the basis of a year of 360 days for each day of the year actually elapsed.

        6.  Payments.  You irrevocably authorize us to effect payments of 
            --------
principal of and interest on all Loans whenever such payment is due and to debit
your designated account for the amount of such payment. We shall furnish to you 
a written confirmation of the amount of each principal and interest payment 
charged against your designated account. You will pay us promptly such amounts 
as may be due if your designated account balance is insufficient. All payments 
of principal and interest on Loans shall be made in the currency of the borrowed
funds in immediately available funds free and clear of and without deduction for
any taxes, fees or other charges of any nature imposed by any governmental
authority, or, if such withholding is required, you shall pay to us the same net
amount as if no withholding was made.

        7.  Payment of Costs.  In addition to the principal and interest
            ----------------
specified in paragraphs 4 and 5, you agree to pay upon demand all costs and
expenses (including reasonable attorneys' fees and legal expenses) we incur in
enforcing the Loans and this Agreement.

        8.  Further Evidence of Loans.  Upon our request, you hereby agree to 
            -------------------------
execute and deliver to us a promissory note or notes payable to our order to 
evidence all or any part of any Loans. If any Loan is or shall be evidenced by 
one or more promissory notes, such note or notes shall be

                                      -2-

 
deemed to incorporate by reference, and to be supplemented and modified by, the 
terms of this Agreement.

     9.   Security. As security for the payment of all sums owed by you to us, 
          --------
we shall have a lien upon, and security interest in, any balance belonging to 
you in any of your deposit or other accounts with us and any other amounts or 
property which from time to time may be owing by us to you or held by us for 
you.

     10.  Defaults. The occurrence of any of the following events shall cause 
          --------
you to be in default on any and all outstanding Loans:

     (a)  the non-payment when due of any amount payable on any of the 
Liabilities and such non-payment continues for five (5) days after such due date
(the term "Liabilities" shall mean all loans and advances made under this 
Agreement and any renewals, extensions and modifications thereof and all of your
other existing and future liabilities, whether absolute or contingent, to the 
Bank regardless of their source or nature and out of whatever transactions 
arising);

     (b)  the failure of any Obligor to observe or perform any other term of 
this Agreement or any other agreement or note with Bank or other lender, 
including without limitation the Loan Agreement and related documents dated June
25, 1996, between Borrower and U.S. Trust (the term "Obligor" includes you and 
all persons otherwise liable for the payment of all such loans or notes or both 
and all renewals, extensions or modifications thereof, such as endorsers or 
guarantors);

     (c)  the entry of any judgment or the issuing of any attachment or 
garnishment against any Obligor in an amount in excess of $150,000.

     (d)  the dissolution, merger, consolidation or reorganization of any 
Obligor;

     (e)  if any information furnished by any Obligor proves to have been 
materially false or misleading when made;

     (f)  the failure of any Obligor to furnish such financial or other 
information as we may reasonably request; and

     (g)  the insolvency of any Obligor, any assignment for the benefit of 
creditors of any Obligor or the filing by or against any Obligor of a petition 
under any provision of any law or statute alleging insolvency or inability to 
pay debts as they mature.

     11.  Acceleration. If you are in default as described in Paragraph 10(a) 
          ------------
through (f), at our election evidenced by notice in writing to you, all Loans, 
whether or not evidenced by a note, shall thereupon become due and payable 
without presentment, demand or protest, all of which are hereby waived. If you 
are in default as described in Paragraph 10(g), then forthwith and without any

                                      -3-

 
election or notice, all Loans, whether or not evidenced by a note, shall 
thereupon become due and payable without presentment, demand, protest or other 
notice of any kind, all of which are hereby waived. You waive all right to stay 
of execution and exemption of property in any action to enforce your obligations
to us hereunder.

     12.  Joint and Several Liability. All of the liabilities shall be joint and
          ---------------------------
several obligations of each of the Borrowers.

     13.  Continuing Effect. This Agreement shall remain in full force and 
          -----------------
effect until all Loans outstanding, together with interest thereon, and all 
other sums required to be paid under the terms of this Agreement have been paid 
in full.

     14.  Governing Law. This Agreement and any note or notes evidencing Loans 
          -------------
made shall be construed in accordance with and governed by the laws of 
Massachusetts.

     15.  Bank's Assignees. The Bank may at any time or from time to time grant 
          ----------------
to others assignments of or participations in the Loans.

     16.  Notices. Any notice given under this Agreement shall be effective on 
          -------
the date when it is delivered to a party at its address set forth as follows (or
at such other address as the party to which may be given may specify to the 
other in writing); if to you, at:

                             Brooks Automation, Inc.
                             15 Elizabeth Drive
                             Chelmsford, MA 01824
                             Attn: Stanley D. Piekos, CFO

and if to us, at:

                 Broad and Chestnut Streets,
                 Philadelphia, PA 19101
                 Attn: R. Thomas Esser
                 F.C. 1-8-4-2

     17.  Miscellaneous. Any failure by us to exercise any right under this 
          -------------
Agreement shall not be construed as a waiver of the right to exercise the same 
or any other right at any other time. If more than one person, including any 
form of legal entity, shall sign this Agreement, as borrower, such persons shall
be jointly and severally liable hereunder and the terms "you" and "your" shall 
be deemed to mean any and all of such persons. The parties hereto intend this 
Agreement to be a sealed instrument and to be legally bound hereby.

                                      -4-

 


                        Acceptance Of And Agreement To
 
            Master Short Term Foreign Currency Borrowing Agreement
            ------------------------------------------------------


     We, the addressee of the above Master Short Term Borrowing Agreement, 
intending to be legally bound, accept and agree to the terms and conditions of 
said Agreement and promise to pay the principal of and interest on all Loans 
made to us by CoreStates Bank, N.A. and all other sums required to be paid by us
to said Bank, under and in accordance with the terms of said Master Short Term
Borrowing Agreement. Signed this 25th day of June 1996.


Brooks Automation, Inc.                  Brooks Automation Canada Corp.

/s/ Stanley D. Piekos                    /s/ Robert J. Therrien
- ---------------------------------        --------------------------------------
     (Borrower)                                 (Borrower)

By: Stanley D. Piekos                    By: Robert J. Therrien   
    -----------------------------            -----------------------------------

    VP & Chief Financial Officer             President & Chief Executive Officer
    -----------------------------            -----------------------------------
     (Name and Title)                            (Name and Title)               



Brooks Automation K.K.                   Brooks Automation Ltd.


/s/ Stanley D. Piekos                    /s/ Stanley D. Piekos            
- ---------------------------------        ---------------------------------
     (Borrower)                               (Borrower)                  
                                         

By: Stanley D. Piekos                    By: Robert J. Therrien   
    -----------------------------            -----------------------------------

    VP & Chief Financial Officer             President & Chief Executive Officer
    -----------------------------            -----------------------------------
     (Name and Title)                            (Name and Title)               


                                      -6-

 


Brooks Automation Massachusetts Securities Corp.


/s/ Stanley D. Piekos
- ---------------------------------------
(Borrower)

By Stanley D. Piekos
   ------------------------------------

   VP & Chief Financial Officer
   ------------------------------------
   (Name and Title)





[SEAL]







                                      -7-