SECURITIES AND EXCHANGE COMMISSION

                 Washington, D. C.  20549


                       SCHEDULE 13D

         Under the Securities Exchange Act of 1934
                             


                INSTRUMENT SYSTEMS COPORATION              
                     (Name of Issuer)

               Second Preferred Stock, Series 1            
              (Title of Class of Securities)

                        457 794 20 4                       
                      (CUSIP Number)

                               with a copy to:
Lauren Rose                    George J. Mazin, Esq.
Taft Securities                Lowenstein, Sandler, Kohl,
225 West Washington              Fisher & Boylan
Suite 2135                     65 Livingston Avenue
Chicago, IL  60606             Roseland, New Jersey  07068
                              (201) 992-8700               
            (Name, Address and Telephone Number
              of Person Authorized to Receive
                Notices and Communications)

                       July 14, 1992                      
           (Date of Event which Requires Filing
                    of this Statement)

If the filing person has previously filed a statement on
Schedule 13G to report the acquisition which is the
subject of this Schedule 13D, and is filing this schedule
because of Rule 13d-1(b)(3) or (4), check the following box
[ ].

Check the following box if a fee is being paid with this
statement [X].  (A fee is not required only if the
reporting person:  (1) has a previous statement on file
reporting beneficial ownership of more than five percent
of the class of securities described in Item 1;  and (2)
has filed no amendment subsequent thereto reporting
beneficial ownership of less than five percent of such
class.  See Rule 13d-7.)


Note:  Six copies of this statement, including
all exhibits, should be filed with the
Commission.  See Rule l3d-1(a) for other parties
to whom copies are to be sent.

* The remainder of this cover page shall be
filled out for a reporting person's initial
filing on this form with respect to the subject
class of securities, and for any subsequent
amendment containing information which would
alter disclosures provided in a prior cover page.

The information required on the remainder of this
cover page shall not be deemed to be "filed" for
the purpose of Section 18 of the Securities
Exchange Act of 1934 ("Act") or otherwise
subject to the liabilities of that section of
the Act but shall be subject to all other
provisions of the Act (however, see the Notes).

                                                 
         

   1)  Names of Reporting Persons (S.S. or
        I.R.S. Identification Nos. of Above
        Persons):

       Taft Securities
                                                 
         

   2)  Check the Appropriate Box if a Member of
        a Group (See Instructions):

    (a)              Not 

    (b)           Applicable
                                                 
         

    3)   SEC Use Only
                                                 
         

    4)   Source of Funds (See Instructions):  WC 
      
                                                 
         

   5)  Check if Disclosure of Legal Proceedings
        is Required Pursuant to Items 2(d) or
        2(e):   

         Not Applicable
                                                 
         

   6)  Citizenship or Place of Organization:

         Illinois      
                                                 
         


                                                 
         

   Number of        7)  Sole Voting Power:         84,500
   Shares Bene-
    ficially        8)  Shared Voting Power:            0 
   Owned by
   Each Report-     9)  Sole Dispositive Power:    84,500
    ing Person
   With:           10)  Shared Dispositive Power:       0 
                                                 
         

   11) Aggregate Amount Beneficially Owned by
        Each Reporting Person:

       84,500
                                                 
         

   12) Check if the Aggregate Amount in Row (11)
        Excludes Certain Shares (See
        Instructions):

         Not Applicable
                                                 
         

   13) Percent of Class Represented by Amount in Row
         (11):     5.03%
                                                 
         

   14) Type of Reporting Person (See
         Instructions):       BD
                                                 
         


ITEM 1.  Security and Issuer.

   The title of the class of equity securities
to which this Schedule 13 (the "Schedule")
relates is Second Preferred Stock, Series 1 (the
"Stock") of Instrument Systems Corporation (the
"Issuer").  

   The name and address of the principal
executive offices of the Issuer are as follows:  

       Instrument Systems Corporation
       100 Jericho Quadrangle
       Jericho, NY  11753

ITEM 2.  Identity and Background.

   The reporting person filing this Schedule is
Taft Securities, an Illinois general partnership
("Taft"), having a principal place of business
at 225 West Washington, Suite 2135, Chicago,
Illinois 60606.  Taft is a registered broker
dealer with the National Association of
Securities Dealers, Inc.  


   The general partners of Taft are: Wellington
Partners Limited Partnership, an Illinois
limited partnership ("Wellington Partners"), and
Wellington Investors Limited Partnership, an
Illinois limited partnership ("Wellington
Investors"), each having a principal place of
business at 225 West Washington, Suite 2135,
Chicago, Illinois 60606.  In addition,
Wellington Investors is the sole general partner
of Wellington Partners.  

   The sole general partner of Wellington
Investors is Kenneth Griffin, a United States
citizen, having a principal place of business at
225 West Washington, Suite 2135, Chicago,
Illinois  60606.  Mr. Griffin's principal
occupation is acting as the general partner of
Wellington Investors.

   Neither Taft, Wellington Partners, Wellington
Investors or Kenneth Griffin has (a) been
convicted, during the last 5 years in a criminal
proceeding (excluding traffic violations or
similar misdemeanors), and (b) been a party to a
civil proceeding of a judicial administrative
body of competent jurisdiction, as a result of
which was or is subject to a judgment, decree or
final order enjoining future violations of, or
prohibiting or mandating activity subject to,
federal or state securities laws or finding any
violation with respect to such laws.

ITEM 3.  Source and Amount of Funds or Other Consideration.

   The Stock is being purchased with the working capital of Taft.

ITEM 4.  Purpose of Transaction.

   Taft intends to own the Stock for investment
purposes only.  Taft has no plans which would
result in any action listed or similar to those
listed in Item 4 of Schedule 13D, except that
Taft may acquire or dispose of securities of the
Issuer in the ordinary course of its business.

ITEM 5.  Interest in Securities of the Issuer.

   A.  Based upon the information contained in
the Issuer's annual report for the fiscal year
ended September 30, 1993, there were issued and
outstanding during 1992 1,680,561 shares of
Second Preferred Stock, Series 1 of the Issuer. 
As of July 14, 1992, Taft owned 84,500 shares of
such Stock, representing 5.03% of the shares of
the Stock outstanding.  

   B.  Taft has the sole power to vote or direct
a vote, and sole power to dispose or direct
the disposition of all of the shares of the
Stock described in paragraph A.


   C.  During the last 60 days, Taft has entered
into the following transactions in the Stock:

                     Type of
Date                 Transaction  Quantity Price

July 13, 1992        Purchase     25,000   $5.9675
July 14, 1992        Purchase      1,000   $5.81
July 14, 1992        Purchase      3,000   $5.935

ITEM 6.  Contracts, Arrangements, Understandings or
         Relationships With Respect to Securities
         of the Issuer.

       Taft has not entered into any contracts,
arrangements, understandings or relationships
with respect to securities of the Issuer.

ITEM 7.  Material To Be Filed As Exhibits.

       Taft is not required to file any exhibit
to this Schedule as described in Item 7 of
Schedule 13D.

                    Signature

       After reasonable inquiry and to the best
of the undersigned's knowledge and belief, the
undersigned hereby certifies that the
information set forth in this statement is true,
complete and correct.

                       January 21, 1994

                       Taft Securities



                       By: /s/ Kenneth Griffin                      
   
                         Kenneth Griffin, in
                               his capacity as sole
                               general partner of
                               Wellington Investors
                               Limited Partnership,
                               a general partner of
                               Taft Securities and
                               the sole general
                               partner of Wellington
                               Partners Limited
                               Partnership, the
                               other general partner
                               of Taft Securities

ATTENTION:  INTENTIONAL MISSTATEMENTS OR
OMISSIONS OF FACT CONSTITUTE FEDERAL CRIMINAL
VIOLATIONS (SEE 18 U.S.C. 1001).