CB/A

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                                  UNITED STATES
                       SECURITIES AND EXCHANGE COMMISSION
                             WASHINGTON, D.C. 20549

                                     FORM CB

                 TENDER OFFER/RIGHTS OFFERING NOTIFICATION FORM
                                (AMENDMENT NO. 4)

Please place an X in the box(es) to designate the appropriate rule provision(s)
relied upon to file this Form:

     Securities Act Rule 801 (Rights Offering)                           [ ]
     Securities Act Rule 802 (Exchange Offer)                            [X]
     Exchange Act Rule 13c-4(h)(8) (Issuer Tender Offer)                 [ ]
     Exchange Act Rule 14d-1(c) (Third Party Tender Offer)               [X]
     Exchange Act Rule 14c-2(d) (Subject Company Response)               [ ]

Filed or submitted in paper if permitted by Regulation S-T Rule 101(b)(8)    [ ]

Note: Regulation S-T Rule 101(b)(8) only permits the filing or submission of a
Form CB in paper by a party that is not subject to the reporting requirements of
Section 13 or 15(d) of the Exchange Act.

                            Drew Scientific Group PLC
    -------------------------------------------- --------------------------
                            (Name of Subject Company)

                                       N/A
        ---------------------------------------------------------- ----
      (Translation of Subject Company's Name into English (if applicable))

                                 United Kingdom
      --------------------------------------------------- ---------------
        (Jurisdiction of Subject Company's Incorporation or Organization)

                              Escalon Medical Corp.
    ------------------------------------------------- ----------------------
                       (Name of Person(s) Furnishing Form)

                  Ordinary Shares of Drew Scientific Group PLC
- ---------------------------------------- ---------------------------------------
                     (Title of Class of Subject Securities)

                                 Not applicable
     ----------------------------------------------------- ---------------
              (CUSIP Number of Class of Securities (if applicable))

   c/o Richard J. DePiano, Chairman and CEO, Escalon Medical Corp., 575 East
Swedesford Road, Suite 100, Wayne, Pennsylvania 19087; telephone: (610) 688-6830
                        (As offeror in the tender offer)
 -------------------------------------------------------------------------------
 (Name, Address (including zip code) and Telephone Number (including area code)
   of Person(s) Authorized to Receive Notices and Communications on Behalf of
                                Subject Company)

              Commencement of exchange offer in the U.K. on 5/14/04
              -----------------------------------------------------
                  (Date Tender Offer/Rights Offering Commenced)

                  PART I - INFORMATION SENT TO SECURITY HOLDERS

ITEM 1.  HOME JURISDICTION DOCUMENTS

Exhibit 1 PRESS RELEASE - Revised Offer by Escalon Medical Corp. ("Escalon") for
          all the Outstanding Share Capital of Drew Scientific Group Plc
          ("drew") Revised Offer Update

ITEM 2.   INFORMATIONAL LEGENDS

          Not applicable.



        PART II - INFORMATION NOT REQUIRED TO BE SENT TO SECURITY HOLDERS

          (1)   Not applicable.

          (2)   No documents are incorporated by reference in the Home
                Jurisdiction Document.



                    PART III - CONSENT TO SERVICE OF PROCESS

          Not applicable.



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                              PART IV - SIGNATURES

         After due inquiry and to the best of my knowledge and belief, I certify
that the information set forth in this statement is true, complete and correct.

                             /s/ Richard J. DePiano
     -----------------------------------------------------------------
                                   (Signature)

           Richard J. DePiano, Chairman and CEO, Escalon Medical Corp.
      ----------------------------- ----------------------------------
                                (Name and Title)

                                  July 12, 2004
      ----------------------------------------------------------------
                                     (Date)




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EX-1

                              EXHIBIT 1 TO FORM CB

9 July 2004

               REVISED OFFER BY ESCALON MEDICAL CORP. ("ESCALON")
                    FOR ALL THE OUTSTANDING SHARE CAPITAL OF
                       DREW SCIENTIFIC GROUP PLC ("DREW")

                              REVISED OFFER UPDATE

On 29 June 2004 Atlantic Law, on behalf of Escalon, announced that Escalon was
revising its offer to 900,000 New Escalon Shares for all of the issued Drew
Shares. The revised Offer Document was posted to Drew shareholders on Friday 2
July 2004.

Recommendation of Revised Offer, Waiver of Acceptance Condition and Proposed
Dealing Facility Atlantic Law, on behalf of Escalon, announces that it has
reached agreement with the Drew Board in the following terms:

In exchange for Drew's recommendation of Escalon's revised Offer, to be
confirmed by separate announcement of Drew, Escalon agrees that its revised
Offer will become unconditional in all respects upon the receipt of valid
acceptances in regard of more than 50% of the Drew Shares. Appendix 1 of the
revised Offer Document is hereby modified accordingly. If declared unconditional
the revised Offer will be kept open for at least 21 days to allow holders of
Drew Options to exercise their rights and accept the revised Offer.

In addition, and in exchange for such recommendation, Escalon agrees to use best
reasonable endeavours to establish a dealing facility through Brewin Dolphin,
Drew's UK brokers, to allow for the trading of New Escalon Shares at no greater
dealing charges than would normally be incurred for the trading of Drew Shares.
Any established dealing facility will be kept open for at least 14 days from
receipt by the Drew shareholder(s) of the Escalon consideration shares. Full
details of any established dealing facility will be posted to Drew shareholders
as soon as possible.

Extension of Revised Offer

Atlantic Law hereby announces that, as at 3.00 p.m. on 9 July 2004, acceptances
of the revised Offer valid in all respects have been received in respect of
1,139,571 Drew Shares, representing approximately 1.28 per cent. of the
existingissued ordinary share capital of Drew.

Atlantic Law, on behalf of Escalon, further announces that the revised Offer is
hereby extended by 7 days, with the consent of Drew and the Panel. The next
closing date will be 1.00pm (London time) on Friday 23 July 2004.

Shareholders of Drew who wish to accept the revised Offer, and who have not done
so, should complete their Form(s) of Acceptance, in accordance with the
instructions printed thereon, whether or not their Drew Shares are in CREST, and
return them, as soon as possible, and in any event so as to be received by post
or during normal business hours by hand to Capita IRG Plc at


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Corporate Actions, PO Box 166, The Registry, 34 Beckenham Road, Beckenham, Kent
BR3 4TH no later than 1.00pm (London time) on Friday 23 July 2004. Additional
Forms of Acceptance are available from Capita IRG Plc, by telephoning 0870 162
3100 (if calling from within the UK) or +44 208 639 2157 (if calling from
overseas).

Neither Escalon nor any person acting, or deemed to be acting, in concert with
Escalon, held any ordinary shares of Drew before the Offer Period or has
acquired or agreed to acquire any such shares during the course of the Offer
Period, other than through the acceptance of the Original Offer and the revised
Offer as described above. None of the acceptances relate to persons acting in
concert with Escalon.

The Escalon Directors accept responsibility for the information contained in
this announcement, which is in accordance with the facts and does not omit
anything likely to affect the import of such information.

Definitions used in the revised Offer Document dated 1 July 2004 apply to this
announcement unless the context otherwise requires.

Enquiries: Atlantic Law
Telephone: 0207 616 2888



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