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                                                                   EXHIBIT 10.24

                                PROMISSORY NOTE


$750,000.00                                              Boston, Massachusetts
                                                               October 9, 1997

      FOR VALUE RECEIVED, the undersigned Augment Systems, Inc., a Delaware
corporation (the "Borrower") hereby promises to pay to the order of FLEET
NATIONAL BANK (the "Bank") the principal amount of Seven Hundred Fifty Thousand
and 00/100 ($750,000.00) Dollars ("Principal"), with interest, at the rate
hereinafter set forth, on the daily balance of all unpaid Principal, from the
date hereof until payment in full of all Principal and interest hereunder. As
used herein, "Letter Agreement" means that certain letter agreement dated August
4, 1997 between the Borrower and the Bank, as amended.

      Interest on all unpaid Principal shall be due and payable monthly in
arrears, on the first day of each month, commencing on the first such date after
the date hereof and continuing on the first day of each month thereafter and on
the date of payment of this note in full, at a fluctuating rate per annum
(computed on the basis of a year of three hundred sixty (360) days for the
actual number of days elapsed) which shall at all times be equal to the sum of
(i) two (2%) percent per annum plus (ii) the Prime Rate, as in effect from time
to time (but in no event in excess of the maximum rate permitted by then
applicable law), with a change in the aforesaid rate of interest to become
effective on the same day on which any change in the Prime Rate is effective.
Overdue Principal and, to the extent permitted by law, overdue interest shall
bear interest at a fluctuating rate per annum which at all times shall be equal
to the sum of (i) four (4%) percent per annum plus (ii) the per annum rate
otherwise payable under this note (but in no event in excess of the maximum rate
permitted by then applicable law), compounded monthly and payable on demand. As
used herein, "Prime Rate" means the variable rate of interest per annum
designated by the Bank from time to time as its prime rate, it being understood
that such rate is merely a reference rate and does not necessarily represent the
lowest or best rate being charged to any customer. If the entire amount of any
required Principal and/or interest is not paid within ten (10) days after the
same is due, the Borrower shall pay to the Bank a late fee equal to five percent
(5%) of the required payment, provided that such late fee shall be reduced to
three percent (3%) of any required Principal and interest that is not paid
within fifteen (15) days of the date it is due if this note is secured by a
mortgage on an owner-occupied residence of 1-4 units.

      All outstanding Principal shall be repaid by the Borrower to the Bank on
February 28, 1998, together with all interest then accrued but unpaid thereon.

      The Borrower may at any time and from time to time, without premium or
penalty, prepay all or any portion of the Principal. Each Principal prepayment
shall be accompanied by payment of all interest on the prepaid amount accrued
but unpaid to the date of payment.

      Payments of both Principal and interest shall be made, in lawful money of
the United States in immediately available funds, at the office of the Bank
located at 75 State Street, Boston, Massachusetts 02109, or at such other
address as the Bank may from time to time designate.






                             


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      The undersigned Borrower irrevocably authorizes the Bank to make or cause
to be made, on a schedule attached to this note or on the books of the Bank, at
or following the time of receiving any payment of Principal, an appropriate
notation reflecting such transaction and the then unpaid balance of Principal.
Failure of the Bank to make any such notation shall not, however, affect any
obligation of the Borrower hereunder or under the Letter Agreement. The unpaid
Principal amount of this note, as recorded by the Bank from time to time on such
schedule or on such books, shall constitute presumptive evidence of the unpaid
principal amount of the Bridge Loan (as defined in the Letter Agreement).

      The Borrower hereby (a) waives notice of and consents to any and all
advances, settlements, compromises, favors and indulgences (including, without
limitation, any extension or postponement of the time for payment), any and all
receipts, substitutions, additions, exchanges and releases of collateral, and
any and all additions, substitutions and releases of any person primarily or
secondarily liable, (b) waives presentment, demand, notice, protest and all
other demands and notices generally in connection with the delivery, acceptance,
performance, default or enforcement of or under this note, and (c) agrees to
pay, to the extent permitted by law, all reasonable costs and expenses,
including, without limitation, reasonable attorneys' fees, incurred or paid by
the Bank in enforcing this note and any collateral or security therefor, all
whether or not litigation is commenced.

      This note is the Bridge Note referred to in the Letter Agreement and is
secured by and entitled to the benefits of the Security Agreement (as defined in
the Letter Agreement). This note is subject to prepayment as set forth in the
Letter Agreement. The maturity of this note may be accelerated upon the
occurrence of an Event of Default, as provided in the Letter Agreement.

      THE BORROWER HEREBY KNOWINGLY, VOLUNTARILY AND INTENTIONALLY WAIVES THE
RIGHT TO A TRIAL BY JURY IN RESPECT OF ANY CLAIM BASED ON THIS NOTE OR ARISING
OUT OF, UNDER OR IN CONNECTION WITH THIS NOTE OR ANY RELATED DOCUMENTS OR OUT OF
ANY COURSE OF CONDUCT, COURSE OF DEALING, STATEMENTS (WHETHER ORAL OR WRITTEN)
OR ACTIONS OF ANY PERSON. THIS WAIVER CONSTITUTES A MATERIAL INDUCEMENT FOR THE
BANK TO ACCEPT THIS NOTE AND TO MAKE THE BRIDGE LOAN AS CONTEMPLATED IN THE
LETTER AGREEMENT.

      Executed, as an instrument under seal, as of the day and year first above
written.


CORPORATE SEAL                            AUGMENT SYSTEMS, INC.


ATTEST:

____________________________              By:__________________________
Secretary                                      Name:
                                                Title:



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