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                                                                  EXHIBIT 10.49

                                 PROMISSORY NOTE

$83,333.00                                                   September 29, 1995


     FOR VALUE RECEIVED, Philip Donnelly, an individual resident of Pennsylvania
(the "Borrower") hereby promises to pay to the order of Safeguard Scientifics
(Delaware), Inc. (the "Lender"), at 800 The Safeguard Building, 435 Devon Park
Drive, Wayne PA 19087 or at such other place in the continental United States as
the Lender may designate in writing, in lawful money of the United States, and
in immediately available funds, the principal sum of Eighty-Three Thousand Three
Hundred Thirty-Three Dollars ($83,333).

     The unpaid principal balance of the Note shall be paid on September 29,
2000.

     The Borrower hereby further promises to pay to the order of the Lender
interest on the outstanding principal amount from the date hereof, at a per
annum rate of 6.35%, compounded annually. Interest shall accrue during the term
of this Note and all accrued interest shall be paid in full upon the payment of
any principal amount of this Note.

     All payments made on this Note (including, without limitation, prepayments)
shall be applied, at the option of the Lender, first to late charges and
collection costs, if any, then to accrued interest, and then to principal.

     Accrued interest and principal shall be prepaid from time to time to the
extent of 25% of the proceeds of any sales or other dispositions (including
redemptions pursuant to that certain Option Shares Escrow Agreement of even date
herewith) by the Borrower of any of the shares of common stock of Core
Technologies (Pennsylvania), Inc. purchased by Borrower from Lender on the date
hereof.

     The accrued interest and outstanding principal amount of this Note may be
prepaid in whole or in part without any prepayment penalty or premium at any
time or from time to time by Borrower upon notice to the Lender.

     Notwithstanding anything in this Note, the interest rate charged hereon
shall not exceed the maximum rate allowable by applicable law. If any stated
interest rate herein exceeds the maximum allowable rate, then the interest rate
shall be reduced to the maximum allowable rate, and any excess payment of
interest made by Borrower at any time shall be applied to the unpaid balance of
any outstanding principal of this Note.



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     An event of default hereunder shall consist of:

     (i) a default in the payment by Borrower to Lender of principal under
this Note as and when the same shall become due and payable;

     (ii) an event of default by Borrower under any other obligation,
instrument, note or agreement with the Lender for borrowed money, beyond any
applicable notice and/or grace period;

     (iii) institution of any proceeding by or against Borrower under any
present or future bankruptcy or insolvency statute or similar law and, if
involuntary, if the same are not stayed or dismissed within sixty (60) days, or
Borrower's assignment for the benefit of creditors or the appointment of a
receiver, trustee, conservator or other judicial representative for Borrower or
Borrower's property or Borrower's being adjudicated a bankrupt or insolvent.

     Upon the occurrence of any event of default, the entire unpaid principal
amount of this Note and all unpaid interest accrued thereon shall, at the sole
option of Lender, without notice, become immediately due and payable, and Lender
shall thereupon have all the rights and remedies provided hereunder or now or
hereafter available at law or in equity.

     The Borrower hereby waives presentment, demand, protest and notice of
dishonor and protest, and also waives all other exemptions; and agrees that
extension or extensions of the time of payment of this Note or any installment
or part thereof may be made before, at or after maturity by agreement by the
Lender. The Borrower shall pay to the Lender, upon demand, all costs and
expenses, including, without limitation, attorneys' fees and legal expenses,
that may be incurred by the Lender in connection with the enforcement of this
Note.

     Any failure by the Lender to exercise any right hereunder shall not be
construed as a waiver of the right to exercise the same or any other right at
any time. No amendment to or modification of this Note shall be binding upon the
Lender unless in writing and signed by it.

     Notices required to be given hereunder shall be deemed validly given (i)
three business days after sent, postage prepaid, by certified mail, return
receipt requested, (ii) one business day after sent, charges paid by the sender,
by Federal Express Next Day Delivery or other guaranteed delivery service, (iii)
when sent by facsimile transmission, or (iv) when delivered by hand:



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     If to Lender:

      Safeguard Scientifics, Inc.
      Attention:  General Counsel
      800 The Safeguard Building
      435 Devon Park Drive
      Wayne, PA  19087


     If to Borrower:

     to the address set forth at the bottom of this Note;

or to such other address, or in care of such other person, as Holder or Borrower
shall hereafter specify to the other from time to time by due notice.

     Any provision hereof found to be illegal, invalid or unenforceable for
any reason whatsoever shall not affect the validity, legality or enforceability
of the remainder hereof.

     This Note shall apply to and bind the successors of the Borrower and shall
inure to the benefit of the Lender, its successors and assigns.

     The Note shall be governed by and interpreted in accordance with the laws
of the Commonwealth of Pennsylvania.

     The Borrower has duly executed this Note as of the date first above
written.


WITNESS:                                   /s/ Philip Donnelly
        -------------------------          ---------------------------------
                                           Philip Donnelly


        Adress:
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