UNITED STATES
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                                  SCHEDULE 14A
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           PROXY STATEMENT PURSUANT TO SECTION 14(A) OF THE SECURITIES
                              EXCHANGE ACT OF 1934

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                              Hercules Incorporated
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                        HERCULES CHAIRMAN RESPONDS TO ISP


Wilmington, DE, April 12, 2001 ... Thomas L. Gossage, Chairman and Chief
Executive Officer of Hercules Incorporated (NYSE: HPC) sent the following letter
to Samuel J. Heyman, Chairman of the Board of International Specialty Products
Inc. (NYSE: ISP):


                                 April 12, 2001

Mr. Samuel J. Heyman
Chairman of the Board
International Specialty Products
1361 Alps Road
Wayne, New Jersey  07470

Dear Mr. Heyman:

      I have received your April 10th letter, which I believe requires a
response. Your letter ends with the statement, "Tom, we want very much to be
constructive here, and if you wish to discuss our ideas for the Company, I am at
your disposal."

      Your letter, together with your previous statements and actions, hardly
indicates a desire to be constructive. I have told you repeatedly that you are
damaging our sale process and our efforts to maximize shareholder value. It is
perfectly understandable why some prospective acquirors may be reluctant to
enter into a transaction with a company that has as its largest shareholder a
dissident engaging in a proxy contest and which could therefore soon have a
split board including your conflicted director nominees.

      I have told you how you may be constructive. It is unfortunate for
Hercules shareholders that you are unwilling to follow that advice and be
constructive.

      Although I cannot prevent you from writing your numerous letters (which I
believe are designed solely to provide you with publicity in your proxy fight),
I will not allow you to mislead the public or our shareholders. In November, I
indicated to you that I was focusing the majority of my time on our efforts to
find a merger partner or purchaser for all or portions of our businesses. I
never said that I did not have the time "to concern" myself "with the tens of
millions of cost savings that could be achieved." In fact, Hercules continues to
focus on both cost savings and the Board's value-maximization process as well as
other challenges confronting the Company in today's difficult environment. We
are proactively addressing all of the items you have mentioned, and many more.


                                                                     (continued)





                                                                               2



      Moreover, to be prudent, we have reactivated our search for a permanent
CEO to be available if conditions warrant, a search that is made much more
difficult by your statements and actions. It should not surprise you to learn
that there are eminently qualified CEO candidates who are concerned about the
issues involved in leading a company in which you hold the largest stock
position and could potentially control one-third of the Board.

      Let me be clear to make sure that there are no misunderstandings. Far from
being constructive, we strongly believe that your actions are destructive -- to
our ongoing sale process, to our search for a permanent CEO, to our focus on the
challenges facing the Company in this difficult environment and to shareholder
value. Unlike you, we have the Company to run and ALL of our shareholders to
protect, and we intend to continue doing so.

                                          Very truly yours,

                                          Thomas L. Gossage


                                      # # #


Hercules manufactures and markets chemical specialties globally for making a
variety of products for home, office and industrial markets. For more
information, visit the Hercules website at www.herc.com.

This news release includes forward-looking statements, as defined in the Private
Securities Litigation Reform Act of 1995, reflecting management's current
analysis and expectations, based on reasonable assumptions. Results could differ
materially depending on such factors as business climate, economic and
competitive uncertainties, failure to complete transactions, adverse legal and
regulatory developments, and adverse changes in economic and political climates
around the world. As appropriate, additional factors are contained in reports
filed with the Securities and Exchange Commission. Readers are cautioned not to
place undue reliance on these forward-looking statements, which speak only as of
the date of this press release. This paragraph is included to provide safe
harbor for forward-looking statements, which are not required to be publicly
revised as circumstances change.

Hercules filed a preliminary proxy statement with the United States Securities
and Exchange Commission on March 12, 2001, as amended on March 16, March 26 and
April 4, 2001, in connection with its 2001 annual meeting of shareholders.
Information regarding the identity of the persons who may, under SEC rules, be
deemed to be participants in the solicitation of Hercules shareholders for the
2001 annual meeting, and their interests in the solicitations, are set forth in
the preliminary proxy statement.

Hercules will be filing a definitive proxy statement and other relevant
documents. WE URGE INVESTORS TO READ THE DEFINITIVE PROXY STATEMENT AND ANY
OTHER RELEVANT DOCUMENTS TO BE FILED WITH THE SEC BECAUSE THEY WILL CONTAIN
IMPORTANT INFORMATION. Security holders may obtain a free copy of the proxy
statement


                                                                     (continued)





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and other related documents filed by Hercules at the SEC's website at
www.sec.gov or at the SEC's public reference room located at 450 Fifth Street,
NW, Washington D.C 20549. Please call the SEC at 1-800-SEC-0330 for further
information on the public reference rooms. When available, the definitive proxy
statement and the other documents may also be obtained from Hercules by
contacting Hercules Incorporated, Attention: Allen Spizzo, Hercules Plaza, 1313
North Market Street, Wilmington, DE 19894-0001, or on Hercules' website at
www.herc.com.



Investor Contact:   Allen A. Spizzo    (302) 594-6491
Media Contact:      John S. Riley      (302) 594-5252