PRELIMINARY PROXY STATEMENT

              AS FILED WITH THE SECURITIES AND EXCHANGE COMMISSION
                                ON MARCH 19, 2001

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                            SCHEDULE 14A INFORMATION
                Proxy Statement Pursuant To Section 14(a) of the
                        Securities Exchange Act of 1934.

Filed by the Registrant [__]
Filed by a Party other than the Registrant [X]

Check the appropriate box:
      [X ] Preliminary Proxy Statement
      [__] Confidential, For Use of the Commission Only (as permitted by Rule
           14a-6 (e) (2))
      [__] Definitive Proxy Statement
      [__] Definitive Additional Materials
      [__] Soliciting Material Under Rule 14a-12

                              HERCULES INCORPORATED

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                (NAME OF REGISTRANT AS SPECIFIED IN ITS CHARTER)

                      INTERNATIONAL SPECIALTY PRODUCTS INC.

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    (NAME OF PERSON (S) FILING PROXY STATEMENT, IF OTHER THAN THE REGISTRANT)

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          0-11.

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NY2:\1022287\21\LWSV20!.DOC\54104.0018


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                                       2


                PRELIMINARY PROXY MATERIALS DATED MARCH 19, 2001
                              SUBJECT TO COMPLETION


                     2001 ANNUAL MEETING OF THE STOCKHOLDERS

                            OF HERCULES INCORPORATED

                            ------------------------




                                 PROXY STATEMENT

                    OF INTERNATIONAL SPECIALTY PRODUCTS INC.

                            ------------------------




                  We are sending this proxy statement to you as one of the
holders of common stock, $25/48 stated value per share, of Hercules
Incorporated, a Delaware corporation, in connection with our solicitation of
your proxy for use at the 2001 Annual Meeting of the Stockholders of Hercules
scheduled for 11:00 A.M., local time, on Thursday, April 26, 2001, at the
Delaware Art Museum, 2301 Kentmere Parkway, Wilmington, Delaware and at any
adjournments or postponements thereof. We are International Specialty Products
Inc., a Delaware corporation, and the largest stockholder of the Company,
beneficially owning approximately 9.9% of Hercules' outstanding shares of common
stock.

                  We are soliciting your proxy to vote at the 2001 Annual
Meeting for the election of our nominees, Samuel J. Heyman, Sunil Kumar, Gloria
Schaffer and Raymond Troubh, as directors of Hercules in the class with a
three-year term continuing until the 2004 Annual Meeting.

THIS PROXY STATEMENT AND THE BLUE PROXY CARD ARE FIRST BEING FURNISHED TO
STOCKHOLDERS ON OR ABOUT MARCH __, 2001.

WE URGE YOU TO SIGN, DATE AND RETURN THE BLUE PROXY CARD IN FAVOR OF THE
ELECTION OF OUR NOMINEES DESCRIBED IN THIS PROXY STATEMENT.

IF YOU HAVE ALREADY SENT A WHITE PROXY CARD TO THE HERCULES DIRECTORS, YOU MAY
REVOKE THAT PROXY AND VOTE AGAINST THE ELECTION OF HERCULES NOMINEES BY SIGNING,
DATING AND RETURNING THE ENCLOSED BLUE PROXY CARD. THE LATEST DATED PROXY IS THE
ONLY ONE THAT COUNTS. ANY PROXY MAY BE REVOKED AT ANY TIME PRIOR TO THE 2001
ANNUAL MEETING BY DELIVERING A WRITTEN NOTICE OF REVOCATION OR A LATER DATED
PROXY FOR THE 2001 ANNUAL MEETING TO GEORGESON SHAREHOLDER COMMUNICATIONS INC.


                                       3


OR TO THE SECRETARY OF HERCULES, OR BY VOTING IN PERSON AT THE 2001 ANNUAL
MEETING. SEE "VOTING PROCEDURES" ON PAGE ___.

















                                       4


                          REASONS FOR OUR SOLICITATION

                  We are asking you to elect our nominees in order to:

         o        assure Board representation with a strong ownership interest
                  and orientation, committed to maximize value for all Hercules
                  stockholders;

         o        bring about the prompt sale of the Company;

         o        urge the Board to remove unwarranted barriers to offers for
                  your shares, so that you can make your own decisions; and

         o        urge the Board to reverse the Company's position with regard
                  to a Hercules Bylaw which it claims requires the affirmative
                  vote of the holders of a majority of all outstanding shares
                  for the election of directors;



THE COMPANY'S PERFORMANCE OVER THE LAST FIVE YEARS HAS, IN OUR OPINION, BEEN
DISASTROUS FOR STOCKHOLDERS.

                  When measured by virtually any financial yardstick, Hercules'
performance over the last five years, has, in our opinion, been disastrous for
the Company's stockholders. Consider the following:

                  o        Hercules' stock price in the last five years has lost
                           nearly 80% of its value since reaching its high of
                           $66.25 on March 19, 1996, wiping out more than $5.5
                           billion in stockholder value, notwithstanding one of
                           the greatest bull markets in the history of the
                           American stock market;

                  o        Based on total return to shareholders over the past
                           one, three, five and 10 years, Hercules was recently
                           (February 26, 2001) ranked by The Wall Street Journal
                           as 6th worst out of 1,000 major public companies;

                  o        Hercules first cut and then totally eliminated your
                           dividend last year despite earlier assurances that
                           the dividend would be maintained;

                  o        Hercules' $3.1 billion acquisition of BetzDearborn in
                           1998 has been characterized by Paul Leming, an ING
                           Barings security analyst, as "one of the worst
                           acquisitions in the history of the chemical industry"
                           (July 18, 2000);

                  o        You should know that all eight of the current
                           incumbent Hercules directors who served on the
                           Hercules Board at the time of the BetzDearborn
                           acquisition in 1998 voted to approve the transaction.
                           Three of the other current Hercules directors are
                           former BetzDearborn directors;



                                       5


                  o        As a result of the BetzDearborn acquisition and the
                           poor operating performance of Hercules' businesses
                           since that time, the Company's debt has increased
                           eleven-fold over the last five years - from less than
                           $300 million, as of the end of 1995, to approximately
                           $3.2 billion, as of December 31, 2000. During that
                           period of time, Hercules' debt ratings have been
                           reduced (six grade levels by Moody's and seven at
                           Standard and Poor's) to non-investment grade -
                           thereby severely impacting the Company's borrowing
                           costs;

                  o        Leslie Ravitz, a chemicals industry security analyst
                           at Morgan Stanley Dean Witter, referring to the
                           continued deterioration in Hercules' financial
                           performance, observed, "It just seems to get worse
                           and worse" (March 23, 2000). Since that time,
                           Hercules' performance has deteriorated even further;
                           and

                  o        Just this past February, Hercules reported fourth
                           quarter 2000 profit from operations of $68 million
                           and a net loss of $6 million, or $0.05 per diluted
                           share, excluding nonrecurring items. This result was
                           in sharp contrast to Hercules' own projection (off
                           more than 30%) given on October 26th, only two months
                           before the end of the quarter, that fourth quarter
                           profit from operations would be in the range of $100
                           million. The results also reflected a significant
                           decline from Hercules' fourth quarter earnings per
                           share of $0.46 in the previous year.

HERCULES HAS DISREGARDED, IN OUR VIEW, THE INTERESTS OF ITS STOCKHOLDERS BY
ERECTING A FORTRESS OF ANTI-TAKEOVER DEFENSES.

                  Hercules has entrenched its Board by erecting over time a
fortress of anti-takeover defenses, which include a poison pill, staggered
board, interpretation of a Company Bylaw to require an affirmative vote of a
majority of all outstanding shares for election of directors, "blank check"
preferred stock, an 80% super majority vote requirement to amend certain Bylaws
and charter provisions and approve certain merger transactions, and the ability
to add directors without stockholder approval.

                  Consider the following examples of how the Hercules Board has
utilized these defenses in disregard, in our opinion, of the interests of its
stockholders:

                  (1) In October 2000, in order to increase our investment in
the Company, we proposed to purchase 25 million additional shares of Hercules
stock for $17.50 per share in cash, a premium of almost 50% over the closing
price on the day before our Hercules share ownership was first publicly
announced. Parenthetically, we made this offer at the same time we recommended
that the Hercules Board entertain a sale of the Company. In so doing, we
acknowledged that "Hercules shares should be worth more in a sale of the
Company," and stated that the offer was an "expression of our confidence" in the
proposed sale course of action and was designed to "provide those Hercules
shareholders who wished to sell their shares now with an opportunity to do so at


                                       6


a 25% premium above the current market price." However, because of the Company's
poison pill our offer required Board consent, and despite repeated requests that
Hercules permit us to proceed, the Board refused to do so.

                  You should know that the Hercules poison pill was adopted last
August notwithstanding the fact that Hercules stockholders have in the past
voiced their strong opposition to poison pills. In 1992, a non-binding proposal
to redeem Hercules' then-existing poison pill, or submit it to a stockholder
vote, was approved by stockholders. Despite this stockholder mandate, the
Hercules Board never put it to a definitive vote and refused to terminate the
pill for three years.

                  With regard to the poison pill currently in effect at the
Company, which has a low 10% threshold, the Hercules Board rushed to adopt it
last year, without shareholder approval, less than two weeks after ISP had
publicly announced its ownership position in Hercules. When we later proposed a
compromise whereby the poison pill would be amended to permit anyone, including
ISP, to purchase up to 20% of the Company's outstanding shares (20% being a more
customary threshold for Companies with poison pills), our proposal was rejected
by the Board; and

                  (2) Similarly, Hercules' disregard for the interests of the
Company's stockholders is demonstrated by a Hercules Bylaw which the Board
claims requires an affirmative vote of the holders of a majority of all
outstanding shares for the election of directors, instead of the greatest number
of votes actually cast at the 2001 Annual Meeting (a plurality vote). This would
mean, for example, that even if each ISP nominee receives 50,000,000 votes and
each incumbent director receives 10,000,000 votes, the incumbents would retain
their seats on the Board because our nominees would not have received a majority
vote of approximately 108 million outstanding shares of Hercules common stock.

                  This voting requirement, we believe, is not only highly
unusual but also disenfranchises stockholders and is inconsistent with good
corporate governance. We do not know of any other public company that has such a
provision. In our view, the Hercules Bylaw, as interpreted by the Company,
serves as a mechanism to entrench the current Board, because if no nominee
receives a majority vote of the outstanding shares, the incumbent directors
would remain in place beyond their three-year term, even if our nominees
received a plurality vote.

                  On February 7, 2001, we called Hercules' attention to this
obvious inequity, whereby a director-nominee could receive a majority of the
votes cast but nevertheless lose the election. On March 8, we requested that
Hercules take the necessary action to remedy this situation, but it has refused
to do so.

                  You should know that in a Delaware News Journal article (March
14, 2000) entitled, "Hercules' Election Method Is Fought", the Hercules voting
requirement provision prompted the following comments from a Wall Street analyst
as well as a corporate governance expert: Gary Hindes, Managing Director of New
York's Deltec Asset Management stated that, "These people [referring to the
Hercules directors] have managed to destroy what was a wonderful company," and


                                       7


is further reported to have stated that Hercules should be asking for the
resignation of its directors, not supporting them for re-election; and Charles
Elson, Director of the Center for Corporate Governance at the University of
Delaware, characterized Hercules' voting provision as "highly unusual" and
further stated, "In all my years [of tracking corporate policies], I have not
seen that with the election of a board."

                  Ask yourself whether these devices are in your best interests.
Why does the Board need so many barriers? You do not need to be "protected" from
making your own decision to sell your shares. YOU should have the ultimate right
to decide. Our nominees will advocate that the Board remove unwarranted barriers
to offers for your shares, so that you can make your own decisions.

THE REVOLVING DOOR AT HERCULES- FOUR CHIEF EXECUTIVES IN A TWENTY-TWO MONTH
PERIOD AND NOW SEARCHING FOR A FIFTH.

                  One of the primary responsibilities of a Company's Board of
Directors is to choose, attract, evaluate, and properly motivate capable chief
executives and retain them for extended periods of time. By this standard of
measurement, in our opinion, the Hercules Board has been extremely unsuccessful,
and we ask you to consider the recent record of chief executive turnover at
Hercules.

                  In 1996, R. Keith Elliott was elected Chief Executive of the
Company. In August, 1998, Elliott and the Hercules Board engineered the
BetzDearborn acquisition which, in our opinion, has been a disaster for the
Company and its stockholders. In October, 1998, William R. Cook, formerly Chief
Executive at BetzDearborn, was elected Hercules' Co-Chief Executive. Within two
months, in December, 1998, Cook abruptly resigned. As Leslie Ravitz, a chemicals
analyst at Morgan Stanley Dean Witter stated at the time, "operating with two
CEO's is a very inefficient strategy [for running] a company." Ravitz went on to
say that Cook and Elliott "were taking too long to make decisions."

                  Shortly thereafter, in May 1999, and less than one year after
the BetzDearborn acquisition, Elliott abruptly "resigned." Parenthetically, in
connection with Elliott's resignation after less than three years as Hercules'
Chief Executive, during which time the Company made the disastrous BetzDearborn
acquisition, he was given a severance package estimated to be worth more than
$14.25 million (not counting the value of accelerated vesting of stock options
and restricted stock grants). This consisted of promised payments of $462,500
per annum for the remaining years of his life plus an additional $500,000 per
annum for the next ten years.

                  Elliott was succeeded by Vincent Corbo who in turn resigned
less than sixteen months later in October, 2000. For Mr. Corbo's performance
during his short tenure as the Company's Chief Executive, Smart Money nominated
him to its "Underachievers Club". The Smart Money article (June 1, 2000),
entitled "Underachievers Club: Chief Executive Obstacle," had this to say about
Mr. Corbo and Hercules' performance on his watch:



                                       8


                  "CEO Vincent Corbo took over on 7/1/99

                  Return since then:  -62.2 percent

                  The facts: This Delaware-based firm has been suffering after
                  an acquisition binge drove debt up to 80 percent of its total
                  capital, nearly three times that of competitors. Corbo has
                  tried to cut the debt by selling off slow-growth divisions.
                  But he's had problems integrating Hercules's biggest
                  acquisition, BetzDearborn, a chemicals maker that until
                  recently used a separate financial tracking system. The
                  result? Confusion on Wall Street, earnings downgrades and
                  research reports with titles such as `More Bad News' and `When
                  Will It End?'

                  The response: `We have already announced significant actions
                  to improve the performance and the value of Hercules,' Corbo
                  says."

                  Thomas Gossage, who had retired as the Company's Chief
Executive in 1996, replaced Corbo last October as "temporary" Chief Executive.
At the time of Mr. Gossage's appointment, the Company announced that it had
begun a nationwide search for a "permanent" Chief Executive with the assistance
of an outside search firm. Since that announcement almost five months ago,
Hercules stockholders have heard nothing further concerning the search for a
permanent chief executive.

                  While Mr. Gossage has, to be sure, immersed himself in the
Company's refinancing and restructuring activities, ask yourself whether
Hercules' operating businesses, with its more than 10,000 employees and 3
billion dollars of sales, could receive proper direction from a temporary chief
executive. Do you believe that the Hercules Board has properly discharged one of
its primary responsibilities - to choose, attract, evaluate, and retain able
chief executives?

                  Finally, chief executive turnover at Hercules has not been
without substantial cost to the Company and its stockholders. In addition to the
cost inevitably associated with extraordinary turnover, Hercules has incurred
costs, in the form of severance and pension payments, which we estimate will
exceed $30 million (not counting the value of pension enhancements, accelerated
vesting of stock options and restricted stock grants and other benefits and
perquisites), in connection with the resignations of four Hercules Chief
Executives in four years.

THE HERCULES BOARD, WE BELIEVE, MUST PROMPTLY SELL THE COMPANY IN ORDER TO
MAXIMIZE STOCKHOLDER VALUES.

                  Management wasted valuable time during the Corbo
administration, in our opinion, pursuing a flawed restructuring strategy. On
October 11, 2000, we wrote the Hercules Board stating that "it has become all
too apparent to us that the course Hercules is now pursuing will not enhance
shareholder value but erode it instead." We went on to recommend that "the
Hercules Board abandon its `too little, too late' approach and promptly
entertain a sale of the Company while the time is still propitious."



                                       9


                  While shortly after our letter, Mr. Corbo resigned and
Hercules elected its current Chief Executive, Thomas Gossage, it was not until
late November that the Company implicitly acknowledged that we were right and
began to pursue a sale. A New York Times article, entitled "Hercules, a Chemical
Maker, to Sell All Its Businesses," observed, "the announcement was a tacit
acknowledgement that Hercules's original plan . . . was unlikely to work."

                  Notwithstanding its sale announcement, the Company's
performance continues to deteriorate, and no sale of the Company is in sight.
What realistic expectation is there that the Hercules Board is sufficiently
committed to realizing the Company's underlying value when, in our opinion, it
has completely failed to do so over the last five years?

WE ARE ASKING YOU TO ELECT A SLATE OF DIRECTORS WITH A STRONG OWNERSHIP INTEREST
AND ORIENTATION, COMMITTED TO MAXIMIZING VALUE FOR HERCULES STOCKHOLDERS.

                  As the owner of more than 10.7 million shares of Hercules
common stock, we have an investment of $150 million at stake. Our interests are
clearly aligned with yours. We want to maximize value for Hercules stockholders.
In contrast, the four incumbent nominee directors up for reelection this year
have in the aggregate purchased for full value only approximately 12,000 shares
(the Hercules nominees have acquired additional shares through outright grants
and Company subsidized stock purchases), worth approximately $162,000 at
current market prices.

                  We seek the opportunity for our nominees to participate
constructively as directors, and particularly with respect to any sale process
involving Hercules. We are not seeking to acquire or control the Company.
Rather, our concern is to safeguard stockholder interests and help ensure that a
sale be executed in an efficient and timely manner for the best price. In our
view, the entrenchment of this Board and the use of the variety of anti-takeover
devices they maintain have not served the interests of the stockholders and
raise serious question as to whether the incumbent directors can provide the
best solution to the Company's problems. Their record speaks for itself.

OUR NOMINEES WILL SEEK TO REMOVE UNWANTED TAKEOVER DEFENSES

         If elected, our nominees will urge the Hercules Board to remove the
anti-takeover devices, which, in our view, threatens to disenfranchise your
voting rights and impede potential takeover bids and offers for your shares. Our
nominees will seek, among other things, to:

                  o        redeem the poison pill rights plan adopted by the
                           Hercules Board last year;

                  o        urge the Board to reverse the Company's position with
                           regard to a Hercules Bylaw which it claims requires
                           the affirmative vote of the holders of a majority of
                           all outstanding shares for the election of directors;



                                       10


                  o        present stockholders with the opportunity to opt out
                           of Section 203 of the Delaware General Corporation
                           Law; and

                  o        resist the adoption of any other measures which could
                           deprive stockholders of the opportunity to make their
                           own decisions.

Our nominees, if elected, will not constitute a majority of the Board. As a
result, our nominees will not be in a position by themselves to cause the
Hercules Board to take the foregoing actions. However, we believe that the
election of our nominees will send a clear message to the remaining incumbent
directors that these actions are necessary and in the best interest of Hercules
stockholders.

                                      --------------------------------------



               QUESTIONS AND ANSWERS ABOUT THIS PROXY SOLICITATION

Q:     WHO IS SOLICITING YOUR PROXY?

A:     We are International Specialty Products Inc. ("ISP"), a New York Stock
       Exchange listed, multinational manufacturer of specialty chemicals and
       mineral products. As of the date of this proxy statement, we are the
       largest stockholder of the Company and beneficially own 10,719,200 shares
       of Hercules common stock, representing approximately 9.9% of the
       outstanding shares. For more information on the participants in our proxy
       solicitation, please see "Certain Information Concerning the
       Participants" on page ___.

Q:     WHO ARE THE ISP NOMINEES?

A:     In addition to Mr. Heyman, the Chairman of ISP's Board, and Mr. Kumar,
       President and Chief Executive Officer of ISP, our nominees include two
       independent persons who are not affiliated with ISP - Gloria Schaffer and
       Raymond Troubh. Gloria Schaffer has served in a number of high profile
       Government positions including the Secretary of State and the
       Commissioner of the Department of Consumer Protection of the State of
       Connecticut and a Member of the Civil Aeronautics Board. Mr. Troubh has
       broad financial experience, with over 25 years in financial consulting,
       which includes serving as a general partner at Lazard Freres & Co. Mr.
       Troubh also served as a governor of the American Stock Exchange. In
       addition, Mr. Troubh has served as a member of the Board of Directors of
       Time Warner, Inc., Becton, Dickinson and Company and America West
       Airlines, Inc. and currently serves as a member of the Board of Directors
       of eight public companies - including Starwood Hotels & Resorts, Inc.,
       Health Net, Inc. and Diamond Offshore Drilling, Inc. If elected to the
       Hercules Board, each ISP nominee would act in accordance with his or her
       fiduciary duties to Hercules stockholders with respect to any action that
       he or she takes as a director. We have no reason to believe that any of
       our nominees will be disqualified or unable or unwilling to serve if
       elected. However, if any of our nominees are unable to serve or for good


                                       11


       cause will not serve, proxies may be voted for another person nominated
       by ISP to fill the vacancy.

Q:     WHO CAN VOTE AT THE 2001 ANNUAL MEETING?

A:     If you owned Hercules shares on March 6, 2001 (the "Record Date"), you
       have the right to vote at the 2001 Annual Meeting. As of the close of
       business on the Record Date, we believe that there were 108,115,824
       shares of common stock of Hercules issued and outstanding and entitled to
       vote. Stockholders have one vote for each share of common stock they own
       with respect to all matters to be considered at the 2001 Annual Meeting.

Q:     WHAT SHOULD YOU DO TO VOTE?

A:     Sign, date and return the enclosed BLUE Proxy card TODAY in the envelope
       provided. For more information on how to vote your shares, please see
       "Voting Procedures" on page ___.

Q:     WHO DO YOU CALL IF YOU HAVE QUESTIONS ABOUT THE SOLICITATION?

A:     Please call Georgeson Shareholder Communications Inc. toll free at
       1-800-223-2064.




                                       12


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                                    IMPORTANT

                  PLEASE REVIEW THIS DOCUMENT AND THE ENCLOSED MATERIALS
CAREFULLY. YOUR VOTE IS VERY IMPORTANT, NO MATTER HOW MANY OR HOW FEW SHARES YOU
OWN.

1.      If your shares are registered in your own name, please sign, date and
        mail the enclosed BLUE Proxy Card to Georgeson Shareholder
        Communications Inc. in the postage-paid envelope provided today.

2.      If you have previously signed and returned a WHITE proxy card to
        Hercules, you have every right to change your vote. Only your latest
        dated card will count. You may revoke any WHITE proxy card already sent
        to Hercules by signing, dating and mailing the enclosed BLUE Proxy Card
        in the postage-paid envelope provided. Any proxy may be revoked at any
        time prior to the 2001 Annual Meeting by delivering a written notice of
        revocation or a later dated proxy for the 2001 Annual Meeting to
        Georgeson Shareholder Communications Inc. or the Secretary of Hercules,
        or by voting in person at the 2001 Annual Meeting.

3.      If your shares are held in the name of a brokerage firm, bank nominee or
        other institution, only it can sign a BLUE Proxy Card with respect to
        your shares and only after receiving your specific instructions.
        Accordingly, please sign, date and mail the enclosed BLUE Proxy Card in
        the postage-paid envelope provided, and to ensure that your shares are
        voted, you should also contact the person responsible for your account
        and give instructions for a BLUE Proxy Card to be issued representing
        your shares.

4.      After signing the enclosed BLUE Proxy Card, do not sign or return the
        WHITE proxy card unless you intend to change your vote, because only
        your latest dated proxy card will be counted.

                  If you have any questions about giving your proxy or require
assistance, please call:

                    Georgeson Shareholder Communications Inc.
                                 17 State Street
                               New York, NY 10004


                         Call Toll-Free: 1-800-223-2064
              Banks and Brokerage Firms Call Collect: 212-440-9800
--------------------------------------------------------------------------------



                                       13


                          BACKGROUND AND RECENT EVENTS

                  ISP began purchasing shares of Hercules common stock in
January 2000 because we believed that the shares of the Company were
substantially undervalued. On July 24, 2000, we filed a Schedule 13D with
respect to our beneficial ownership of approximately 9.98% of the outstanding
common stock of Hercules and informed the Company's former Chairman and CEO,
Vincent Corbo, that we wished to increase our ownership position and were filing
a Hart-Scott-Rodino application seeking permission to do so.

                  On August 1, 2000, Hercules released its second quarter 2000
earnings, which reported that net income had fallen 56% from the previous
quarter.

                  On August 4, 2000, less than two weeks after we filed our
Schedule 13D, the Hercules Board adopted the poison pill Rights Agreement. The
Board, in taking this action, defied the wishes of Hercules stockholders as
evidenced by the adoption of a non-binding proposal to redeem Hercules' previous
pill in 1992. The poison pill serves as a powerful anti-takeover device by
making it prohibitively expensive to acquire 10% or more of Hercules' common
stock without Board approval.

                  On August 25, 2000, Hercules announced that it was reducing
its quarterly dividend from $0.27 to $0.08 per share. The dividend was totally
eliminated on November 14, 2000.

                  On October 11, 2000, Mr. Heyman proposed that ISP commence a
tender offer for 25 million shares of Hercules common stock at $17.50 per share
in cash. This price represented a premium of over 22% based on the Hercules
closing price of $14.31 per share on October 10, 2000, and an almost 50% premium
over the Hercules closing price of $11.75 per share on July 21, 2000, the day
before our first public filing stating that we had acquired a 9.9% interest in
Hercules. In connection with ISP's proposal, Mr. Heyman delivered the following
letter to the Board on October 11, 2000, encouraging the Board to abandon
management's restructuring plan.

             Dear Hercules Board member:

                      As you no doubt are aware, Vince Corbo and I have had a
             number of discussions in recent weeks regarding Hercules'
             restructuring program. In this regard, I was surprised to learn
             from Vince yesterday that, notwithstanding the recent Moody's
             downgrade of the Company's debt as well as other developments
             referred to below, Hercules does not intend to alter its current
             course. Parenthetically, the downgrade, coming at a particularly
             turbulent time in the high yield market (I am enclosing an October
             10th, The Wall Street Journal article entitled, "Junk-Bond Prices
             Shrink As Investor Caution Grows," regarding this subject), will
             now result in a very costly refinancing for the Company -- thereby


                                       14


             making it impossible for Hercules to achieve anywhere near the
             interest savings previously projected.

                      While Hercules' game plan may have made good sense when
             first adopted, we are convinced that adverse developments in recent
             months have now overtaken it. Accordingly, for Hercules to proceed
             now with a "too little, too late" program raises serious question
             as to whether the Company is pursuing a strategy which
             discriminates in favor of its creditors at the expense of its
             shareholders.

                      Consider these recent developments:

                      (1)  Significant delays in asset dispositions, including
                           the real possibility that FiberVisions will not be
                           sold at this time;
                      (2)  Decline in growth forecasts for core operations;
                      (3)  Reduction in size of acquisition program;
                      (4)  Significant decline in projected interest rate
                           savings;
                      (5)  Adverse impact of the euro, which is especially
                           significant for Hercules given its substantial
                           European presence;
                      (6)  Decline in overall earnings projections; and
                      (7)  Drastic dividend reduction.

                      In the face of these developments, it has become all too
             apparent to us that the course Hercules is now pursuing will not
             enhance shareholder value but erode it instead. What justification
             can there be for making asset divestitures which are earnings
             dilutive, and which in the end, because of the credit downgrade as
             well as other factors, will not be sufficient to enable Hercules to
             achieve sufficient financial flexibility to grow its remaining
             businesses at anywhere near the targets the Company established
             only several months ago? Under all the circumstances and given the
             fact that private sale values of specialty chemicals businesses are
             still robust and well above public trading values, we have come to
             the conclusion that the only practicable option for realizing
             Hercules' underlying values must involve the sale of the Company,
             in whole or in parts.

                      Also of serious concern to us is Hercules' apparent
             disregard for the interest of its shareholders, as demonstrated by
             its adoption of a "poison pill" on August 7th, which provides for a
             10% trigger point. Significantly, the Board adopted this
             anti-shareholder provision little more than 2 weeks after we had
             notified Vince that we had acquired 9.9% of Hercules' shares,
             informing him at the same time that we wished to increase our
             ownership position and were filing a Hart-Scott Rodino application


                                       15


             seeking permission to do so. Moreover, Hercules' refusal to
             eliminate or modify its "poison pill" in the face of our offer of a
             standstill agreement is further indicative of Hercules'
             anti-shareholder bias.

                      We are therefore requesting that the Hercules Board
             abandon its "too little, too late" approach and promptly entertain
             a sale of the Company while the time is still propitious. And the
             timing here is all the more important in light of the fact that
             Hercules is about to embark on a major refinancing, which we
             anticipate could become extremely expensive to unwind should
             Hercules decide to pursue a sale of the Company at a later time.

                      In the meantime, as an expression of our confidence in
             this proposed course of action and to provide those Hercules
             shareholders who wish to sell their shares now with an opportunity
             to do so at a 25% premium above the current market price, we are
             prepared to commence a tender offer for 25 million shares of
             Hercules common stock at $17.50 per share in cash. While we believe
             that Hercules' shares should be worth more, in a sale of the
             Company, than our tender offer price, this price represents an
             almost 50% premium over Hercules' closing price of $11.75 per share
             on July 21st, the day before ISP's 13D filing providing notice for
             the first time that it had acquired a 9.9% interest in Hercules.
             ISP's tender offer will not be subject to financing but will
             obviously require that the Hercules Board exempt our offer from the
             "poison pill" and approve ISP's purchase of shares for purposes of
             Section 203 of the Delaware General Corporation Law.

                      We are prepared to commence the tender offer promptly
             should you inform us that you will meet the above conditions. We
             would appreciate your timely response.

                              Sincerely,

                              /s/ Samuel J. Heyman

                  On October 11, 2000, Hercules issued a press release
indicating that it had received ISP's letter and that the Board would consider
ISP's proposal. Soon thereafter, on October 17, 2000, Vincent Corbo resigned as
Chairman and CEO of Hercules and Thomas Gossage was named its new Chairman and
CEO. Mr. Gossage stated that Hercules "will consider all strategic alternatives,
as well as the proposal made by Mr. Heyman, based on our considered view of what
is in the best interest of all Hercules shareholders." At the same time,
Hercules announced that it did not expect to meet analysts earnings estimates
for its third quarter ending September 30, 2000.



                                       16


                  On November 28, 2000, Hercules announced that its Board had
decided to consider the sale or merger of the Company. Mr. Gossage stated that
"the best strategic path for the Company over the long-term is to become part of
a larger enterprise" and that "moving forward on this path provides the maximum
value and opportunity for our shareholders, employees and customers."

                  On January 18, 2001, Hercules announced that it had ended
discussions on the sale of its FiberVisions Unit. Shortly thereafter, on January
23, 2001, Hercules debt was downgraded by Standard & Poor's.

                  After receiving no response to our proposal made on October
11, 2000, and in light of the adverse developments at the Company described
above, on January 23, 2001, ISP reiterated its proposal to make an offer to
purchase 25 million shares of Hercules common stock at a price of $17.50 per
share in cash if, as requested by Mr. Heyman, the Hercules Board would exempt
the offer from the poison pill and approve ISP's purchase of shares for purposes
of Section 203 of the Delaware General Corporation Law. In connection with ISP's
proposal, Mr. Heyman delivered the following letter to Mr. Gossage on January
23, 2001:

              Dear Tom:

                      Confirming yesterday's telephone conversation, I have
              reiterated ISP's interest in proceeding with its tender offer
              first proposed to the Hercules Board last October. Notwithstanding
              a number of adverse developments at the Company, as well as the
              substantial deterioration of the U.S. economy in recent months, we
              are still willing to proceed on the same basis -- at the original
              price of $17.50 per share in cash for 25 million shares of
              Hercules common stock.

                      Given the delay with respect to execution of the Company's
              program and uncertainty as to its outcome, we believe that a
              substantial number of Hercules shareholders may very well wish to
              avail themselves of the opportunity to sell their shares, or a
              portion thereof, at what amounts to a 30% premium above the
              current market price and an almost 50% premium over Hercules'
              closing price of $11.75 per share on July 21st, the day before
              ISP's 13D filing providing notice for the first time that it had
              acquired a 9.9% interest in Hercules. As we have stated earlier,
              ISP's tender offer will not be subject to financing but will
              obviously require that the Hercules Board exempt our offer from
              the "poison pill" and approve ISP's purchase of shares for
              purposes of Section 203 of the Delaware General Corporation Law.
              We are prepared to commence the tender offer promptly should you
              inform us that you will meet these conditions.



                                       17


                      Finally, ISP's proposed course of action is perfectly
              consistent with Hercules' ongoing effort to maximize shareholder
              values. In this connection, you can always rely on the fact that
              we will be constructive with respect to any actions favorable to
              all Hercules shareholders. Moreover, time is of the essence here.
              As you know, Tom, we have been extremely patient due in no small
              measure to your reassurance to Hercules shareholders over recent
              months as well as our desire to be constructive. Now, of course,
              Hercules' continued optimistic prognostications over the past year
              have yet to be realized, the economic environment deteriorates
              with each passing day, and we must be allowed to proceed
              expeditiously so that we can hold the price in place.

                      I would appreciate your prompt response.

                      All the best.

                                                        Sincerely,

                                                        /s/ Samuel J. Heyman

                  After still receiving no response to our tender offer proposal
made on October 11, 2000, and reiterated on January 23, 2001, Mr. Heyman
delivered the following letter to Mr. Gossage on February 7, 2001:

              Dear Tom:

                      I am very disappointed that, notwithstanding our attempt
              to impress upon you the urgency that ISP be permitted to proceed
              with its tender offer, now more than two weeks later we still have
              not received your Board's response. Apparently, it has decided to
              await the results of Hercules' divestiture program, which we
              believe is a serious mistake. Moreover, as I indicated to you, it
              is just not realistic to expect us to keep our offer in place
              indefinitely, especially when the Company can clearly pursue its
              divestiture program while permitting our offer to go forward at
              the same time.

                      Unless you promptly communicate that we can proceed with
              the tender offer, we would now request that Hercules consider an
              alternative ISP initiative - which would be to amend the threshold
              for the Company's poison pill from the current 10% to 20% (the
              latter being a more customary threshold for companies with poison
              pills) and approve any party's purchase of shares up to the 20%
              threshold for purposes of Section 203 of the Delaware General
              Corporation Law. While you have indicated that you share our
              philosophic opposition to poison pills altogether, this more
              limited, compromise approach is designed to hopefully elicit your


                                       18


              Board's prompt affirmative response and would at least permit ISP,
              or anyone else for that matter, to make purchases up to a 20%
              limitation.

                      If the Hercules Board refuses to take this action
              voluntarily, we intend to seek a vote of Hercules shareholders at
              this year's Annual Meeting to repudiate the Company's poison pill.
              In this connection, we believe that if the Company will not act
              responsibly, its shareholders should be able to decide. If you
              require us to proceed in this fashion, we are requesting that the
              Hercules Board include the various proposals in the attached
              letter in your proxy materials for this year's Annual Meeting.
              Should the Board refuse this request, the attached letter serves
              as formal notification pursuant to Section 14 of the Securities
              Exchange Act of 1934, which we have been advised must be provided
              no later than today.

                      As you can see, we have included a proposal whereby
              Hercules would opt out of the provisions of Section 203 of the
              Delaware General Corporation Law, as well as various housekeeping
              proposals, and have included a proposal relating to the
              methodology used to elect directors. In this later connection, we
              believe that Hercules Bylaws, which your Company claims require
              "the affirmative vote of a majority of the outstanding shares" to
              elect directors, is highly unusual and serves no purpose other
              than as an entrenchment device. Most companies require only a
              majority of the shares voted (a plurality). Under your
              interpretation of the bylaws, a nominee could receive a majority
              of the votes cast but nevertheless lose the election.

                      All the best.

                                   Sincerely,

                              /s/ Samuel J. Heyman

                  Just this past February, Hercules reported fourth quarter 2000
profit from operations of $68 million and a net loss of $6 million, or $0.05 per
diluted share, excluding nonrecurring items. This result was in sharp contrast
to Hercules' own projection (off more than 30%) given on October 26th, only two
months before the end of the quarter, that fourth quarter profit from operations
would be in the range of $100 million. The results also reflected a significant
decline from Hercules' fourth quarter earnings per share of $0.46 in the
previous year.

                  On February 8, 2001, almost four months after our initial
proposal, Hercules said that it would consider ISP's tender offer "in due
course." Mr. Gossage also told analysts on February 8, 2001 that he was working
toward a sale of the Company by midyear, but declined to provide details on the
process.



                                       19


                  In light of the Company's failure to respond to ISP's repeated
requests that the Company terminate its poison pill, or in the alternative amend
the poison pill's threshold from 10% to 20%, Mr. Heyman delivered the following
letter to Mr. Gossage on February 20, 2001:

              Dear Tom:

                      Despite our repeated requests that Hercules eliminate its
              poison pill (or, in connection with a proposed compromise, at
              least increase its trigger point to 20%) to enable ISP (or anyone
              else for that matter) to increase its ownership of your Company's
              shares - which requests date back to September, 2000, and have
              been repeated in letters dated October 11, January 23, and most
              recently on February 7 - we continue to receive no response from
              you or your Board.

                      Since we became a shareholder early last year, the Company
              and its shareholders have in our opinion paid a high price for
              management's procrastination as well as its continued flawed
              policies and poor execution. We are also shocked and surprised by
              the Company's continued withholding of information from its
              shareholders and what we consider to be its remarkable
              indifference to their concerns - as was plainly evidenced by the
              Company's recent conference call.

                      Under the circumstances, we believe that you have left us
              no alternative but to wage a proxy contest at the Company's Annual
              Meeting this Spring. In addition to the previous notification we
              have given regarding proposals to be presented for action at the
              Meeting, we will also be nominating a slate of Directors to run
              for the four Board seats whose terms expire this year,
              director-nominees who, I can assure you, will be committed to the
              maximization of values for all Hercules shareholders.

                                   Sincerely,

                              /s/ Samuel J. Heyman

                  The Hercules Board failed to respond to ISP's repeated
requests (on October 11, 2000, January 23, 2001 and February 7, 2001) that
Hercules eliminate or revise its poison pill to enable ISP to promptly proceed
with its proposed tender offer.

                  On February 23, 2001, Mr. Gossage sent a letter to Mr. Heyman
stating, among other things, that the Board had declined to amend the Hercules
Shareholder Rights Plan to permit an acquiror to purchase up to an additional
10% of the Company's shares beyond the current 10% threshold.



                                       20


                  In response to Mr. Gossage's February 23 letter, Mr. Heyman
sent Mr. Gossage the following letter on February 28, 2001:

              Dear Tom:

                      I was disappointed in your February 23rd letter and your
              Board's decision to reject ISP's compromise proposal. Contrary to
              your apparent belief, there is nothing inconsistent in our view
              with a shareholder being permitted to underscore its confidence in
              the underlying values of the Company by making an additional
              investment on the one hand and your "on going sale process" on the
              other.

                      We are concerned with what seems to us Hercules' narrow,
              one-dimensional approach to maximizing shareholder values. If
              Hercules is unable to sell the Company on an advantageous basis,
              it will have needlessly deprived Hercules shareholders of the
              opportunity to decide for themselves whether to accept our
              previously proposed $17 1/2 tender offer or, under our compromise
              approach, sell their shares in the open market to ISP or any other
              shareholder wishing to acquire up to 20% of the Company's shares.
              This position is especially surprising given the multitude of
              takeover defenses the Company has erected and the fact that we
              have always been willing to address any of your legitimate
              concerns in the form of reasonable conditions with respect to our
              ownership position.

                      With respect to your reference to the withdrawal of our
              proposed tender offer, as you know, the October offer expired by
              its own terms on account of the fact that your Board had refused
              to exempt it from its poison pill and related Delaware statutory
              provisions. That is why we put forward the compromise proposal to
              permit ISP to acquire up to 20% of Hercules' shares rather than
              35%. While we can only assume that if your Board is unwilling to
              permit our acquisition of up to 20% of Hercules shares, it would
              not have gone along with our 35% proposal either - but if we are
              missing something in this regard, please let us know.

                      With regard to the last point in your letter, your claim
              that ISP's actions/statements are a hindrance to your efforts is
              sheer nonsense, as in point of fact we have been very patient and
              constructive shareholders for some time now. As you will recall,
              it was ISP who first encouraged Hercules to abandon its flawed
              restructuring strategy and sell the Company. While it took
              Hercules quite some time to adopt this strategy, we not only
              applauded the decision but have provided assurances, whether we
              were a 10%, 20%, or 35% owner, that we would support the sale of


                                       21


              the Company at a fair price. In fact, despite your invitation, we
              have refrained from taking part in the auction process in large
              measure because we view our Hercules stake as an investment and so
              that there could be no claim that our participation, as the
              Company's major shareholder, would have a chilling effect on other
              interested bidders.

                      Tom, you know that we have a high conviction concerning
              the way in which Hercules has conducted the Company's affairs in
              recent years. In this connection, we intend to bring these matters
              to the attention of Hercules shareholders at the Company's
              upcoming Annual Meeting. Moreover, as owners of more than 10.7
              million Hercules shares, we will be seeking to elect a slate of
              directors, with a strong ownership orientation committed to the
              interests of Hercules shareholders, to replace the four incumbent
              directors up for re-election this year, who we understand (as of
              the last public filing) own in the aggregate less than 50,000
              shares.

                                   Sincerely,


                                   /s/ Samuel J. Heyman


         On March 5, 2001, Mr. Heyman sent the following letter to Mr. Gossage:


              Dear Tom:

                      Just a note to close the loop with you regarding the
              discussions between our General Counsel, Rich Weinberg, and your
              David Katz.

                      When I received your February 23rd letter, although I do
              not believe for a minute that we are in any way hindering your
              efforts to sell the Company, in an effort to bend over backwards,
              I asked Rich to contact David to see whether there was anything we
              could do to be helpful. Rich and David met on February 26th and
              talked on the telephone several days later, during which time we
              were requested to delay the filing of our preliminary proxy
              materials.

                      We suggested, and quite appropriately I believe, that if
              you wanted us to delay our filing for some period, we would be
              willing to accommodate you so long as there was a similar
              adjustment to the Annual Meeting date. Obviously, we cannot be put
              in the position of delaying our filing and as a result SEC
              clearance of our materials while at the same time Hercules
              reserves its right to press forward with its April 26th Annual
              Meeting date. And so we were completely floored when David got
              back to us to indicate that this was apparently what you had in
              mind.



                                       22


                      Tom, we attempted to respond to your stated concerns, but
              the upshot of these discussions is that you have left us no
              alternative but to proceed with our filing, which should take
              place later today.

                                   Sincerely,

                                   /s/ Samuel J. Heyman


                On March 8, 2001, Samuel J. Heyman sent the following letter to
        Mr. Gossage:

              Dear Tom:

                      Although I wrote you on February 7th regarding your
              Company's director election by-law, which requires, according to
              Hercules' interpretation, an affirmative vote of a majority of the
              outstanding shares for election of directors, we have received no
              response concerning this matter.

                      We have been advised that this by-law, as interpreted by
              your Company, is to say the least highly unusual and indeed may be
              unique in the annals of corporate governance. Moreover, it could
              well operate to disenfranchise Hercules shareholders by bringing
              about an unfair result whereby an ISP nominee, by way of example,
              could receive votes representing 50 million Hercules shares to 10
              million shares for the incumbent, and under your Company's by-law,
              the incumbent would retain his or her seat on the Board.

                      Tom, I think you would acknowledge that this would be an
              outrageous result, and I would request that you and your Board
              promptly take whatever action is necessary to remedy this -
              thereby taking this issue off the table so that we can all focus
              in our proxy contest on the real issues of concern to Hercules
              shareholders.

                      Inasmuch as the Annual Meeting is scheduled to take place
              in April, I would appreciate your prompt response.

                      Thank you for your anticipated cooperation in this matter.

                                   Sincerely,

                                   /s/ Samuel J. Heyman




                                       23


                On March 12, 2001, Samuel J. Heyman sent the following letter to
        Mr. Gossage:

              Dear Tom:

                      We have not received a response to our February 7 and
              March 8 letters concerning the director election Bylaw matter. I
              can only assume that this matter has been referred to your Board
              for its determination, and from past experience I must tell you,
              quite frankly, that I simply have no confidence in the willingness
              of the Hercules Board to do the right thing.

                      And this brings us to a second point. In reviewing past
              actions of the Hercules Board, which in our opinion evidence a
              clear disregard for the rights and interests of the Company's
              shareholders, we simply cannot be sure that a favorable vote on
              resolutions currently included in our Preliminary Proxy Statement
              will be implemented by your Board without costly and time
              consuming delay and even possible litigation. For example, what
              possible explanation could there be for the following:

                               In 1992, a non-binding proposal to redeem
                      Hercules' then existing, 20% threshold poison pill or
                      submit it to a stockholder vote was approved by
                      stockholders. Despite this stockholder mandate, the
                      Hercules Board never put it to a definitive vote and
                      refused to terminate the pill for three years. And then to
                      add insult to injury, notwithstanding the 1992 stockholder
                      vote, the Hercules Board implemented just this past
                      August, without notice or shareholder approval, a new
                      poison pill with a low 10% threshold.

                      In view of the above, we have decided to table our other
              shareholder proposals in order to focus the proxy contest on the
              election of our nominees. As a result, both sides will be able to
              address for shareholders, in a very direct and clear cut way, the
              paramount issue - the Hercules Board's record of corporate
              stewardship.

                                   Sincerely,


                                   /s/  Samuel J. Heyman



                                       24


                              ELECTION OF DIRECTORS

                  We are soliciting your proxy for the election of the ISP
nominees as directors of the Company to serve until the 2004 Annual Meeting of
Stockholders and until their successors are duly elected and qualified.

                  In accordance with Hercules Restated Certificate of
Incorporation and Bylaws and the Delaware General Corporation Law, Hercules
Board of Directors is to consist of not less than seven and not more than
eighteen Directors, the exact number to be specified by the Board. The Directors
are to be divided into three classes as nearly equal in number as possible. At
each annual meeting of stockholders, members of one of the classes, on a
rotating basis, are elected for a three-year term. Based on information
contained in reports filed by the Company with the Securities and Exchange
Commission, thirteen directors currently serve on the Hercules Board. Four of
these directors have terms that expire in 2001 and, according to the Company's
proxy statement for the 2001 Annual Meeting, four directors are to be elected at
the 2001 Annual Meeting and one director, Robert G. Jahn, will be retiring upon
the expiration of his term. Messrs. Heyman, Kumar, Gloria Schaffer and Raymond
Troubh, if elected, would serve for terms expiring at the Company's annual
meeting of stockholders in 2004. If any additional directorships are to be voted
upon at the 2001 Annual Meeting, we reserve the right to nominate additional
persons to fill such positions. We do not expect that the ISP nominees will be
unable to stand for election but, in the event that any ISP nominee is unable to
do so, shares represented by BLUE proxy cards will be voted for the other ISP
nominees. In addition, ISP reserves the right to nominate substitute or
additional persons if the Company makes or announces any changes to its Bylaws
or takes or announces any other action that has, or if consummated would have,
the effect of disqualifying any of the ISP nominees.

                  If the ISP nominees are elected and take office as directors,
they intend to discharge their duties as directors of the Company in compliance
with all applicable legal requirements, including the general fiduciary
obligations imposed upon corporate directors.

ISP NOMINEES

                  The information below concerning age, principal occupation and
directorships has been furnished by each respective nominee. The following
persons are our nominees for election as directors in the class whose terms
expire at the 2004 Annual Meeting of Stockholders:


                                          Present Principal Occupation and Five Year
Name and Business Address        Age      Employment History                                        Class
-------------------------        ---      ------------------                                        -----
                                                                                            
Samuel J. Heyman                  62      Mr. Heyman has been a director and Chairman of ISP       2004
1361 Alps Road                            since its formation and served as its Chief Executive
Wayne, New Jersey 07470                   Officer from its formation until June 1999. He also


                                       25


                                          has been a director of GAF Corporation ("GAF") and its
                                          successor by merger, G-I Holdings Inc. ("G-I
                                          Holdings"), for more than five years and was President
                                          and Chief Executive Officer of GAF and certain of its
                                          subsidiaries and Chief Executive Officer of G-I
                                          Holdings for more than five years until September
                                          2000. G-I Holdings primary business is conducted
                                          through Building Materials Corporation of America
                                          ("BMCA"), an indirect, approximately 97% - owned
                                          subsidiary of G-I Holdings which is primarily engaged
                                          in the commercial and residential roofing business. In
                                          January 2001, G-I Holdings filed for protection under
                                          chapter 11 of the United States Bankruptcy Code as a
                                          result of its asbestos liabilities. Mr. Heyman was a
                                          director and Chairman of BMCA from its formation until
                                          September 2000, and served as Chief Executive Officer
                                          of BMCA from June 1996 to January 1999 and from July
                                          1999 to September 2000 and as the President of BMCA
                                          from July 1999 to February 2000. He is also the Chief
                                          Executive Officer, Manager and General Partner of a
                                          number of closely held real estate development
                                          companies and partnerships whose investments include
                                          commercial real estate and a portfolio of publicly
                                          traded securities.

Sunil Kumar                       50      Mr. Kumar has been director, President and Chief           2004
1361 Alps Road                            Executive Officer of ISP since June 1999.  Mr. Kumar
Wayne, New Jersey 07470                   has also been President and Chief Executive Officer of
                                          certain subsidiaries of ISP, including ISP Investments
                                          Inc., since June 1999.  Mr. Kumar was a director,
                                          President and Chief Executive Officer of BMCA from May
                                          1995, July 1996 and January 1999, respectively, until
                                          June 1999.  He was Chief Operating Officer of BMCA
                                          from March 1996 to January 1999.  Mr. Kumar also was
                                          President, Commercial Roofing Products Division, and
                                          Vice President of BMCA from February 1995 to March
                                          1996.


                                       26


Gloria Schaffer                   70      Ms. Schaffer served as a Commissioner of the               2004
1211 Chapel St.                           Department of Consumer Protection of the State of
New Haven, CT  06511                      Connecticut from 1991 to 1995, as a Member of the
                                          Civil Aeronautics Board from 1978 to 1984 and as the
                                          Secretary of State of the State of Connecticut from
                                          1970 to 1978.  Ms. Shaffer also previously served on
                                          the Board of Directors of Amity Bank and Amity
                                          Bankcorp, Mott's Inc. and Emery Air Worldwide, and,
                                          since 1996, has served as a partner at C.A. White,
                                          Inc., a real estate development firm.

Raymond S. Troubh                 74      Mr. Troubh has been a financial consultant for more        2004
10 Rockefeller Plaza                      than five years.  Prior to that he was a general
Suite 712                                 partner of Lazard Freres & Co., an investment banking
New York, New York 10020                  firm, and a governor of the American Stock Exchange.
                                          Mr. Troubh has served as a director of the following
                                          public companies: Time Warner, Inc., Becton, Dickinson
                                          and Company and America West Airlines, Inc., and is a
                                          director of ARIAD Pharmaceuticals, Inc., a
                                          biopharmaceutical company, Diamond Offshore Drilling,
                                          Inc., a contract drilling company, General American
                                          Investors Company, an investment trust company,
                                          Gentiva Health Services, Inc., a healthcare provider,
                                          Health Net, Inc., a managed healthcare company,
                                          Starwood Hotels & Resorts, Inc., a hotel operating
                                          company, Triarc Companies, Inc., a holding company,
                                          and WHX Corporation, a steel products company.  He is
                                          also a trustee of Corporate Renaissance Group
                                          Liquidating Trust, Inc., MicroCap Liquidating Trust
                                          and Petrie Stores Liquidating Trust.

                  Each of the nominees has consented to serve as a director
until the expiration of his or her respective term and until such nominee's
successor has been elected and qualified or until the earlier resignation or
removal of such nominee. We have no reason to believe that any of the nominees
named above will be disqualified or unable or unwilling to serve if elected.
However, if any of the nominees are unable to serve or for good cause will not
serve, proxies may be voted for another person nominated by ISP to fill the
vacancy.


                                       27


                  The nominees understand that, if elected as directors of
Hercules, each of them will have an obligation under Delaware law to discharge
his or her duties as a director in good faith, consistent with his or her
fiduciary duties to Hercules and its stockholders.

                       WE STRONGLY RECOMMEND THAT YOU VOTE
                       "FOR" THE ELECTION OF OUR NOMINEES.


                         OTHER MATTERS TO BE CONSIDERED
                           AT THE 2001 ANNUAL MEETING

RATIFICATION OF APPOINTMENT OF INDEPENDENT AUDITORS

                  As set forth in Hercules' proxy statement, at the 2001 Annual
Meeting, Hercules stockholders will be asked to ratify the appointment by
Hercules Board of PricewaterhouseCoopers LLP as Hercules' independent auditors
for the year 2001. We are not making any recommendation on this proposal.

OTHER PROPOSALS

                  Except as set forth above, we are not aware of any proposals
to be brought before the 2001 Annual Meeting. However, we intend to bring before
the 2001 Annual Meeting such business as may be appropriate, including without
limitation nominating additional persons for directorships, or making other
proposals as may be appropriate to address any action of Hercules Board not
publicly disclosed prior to the date of this proxy statement. Should other
proposals be brought before the 2001 Annual Meeting, the persons named as
proxies in the enclosed BLUE proxy card will vote on such matters in their
discretion.

                                VOTING PROCEDURES

                  In order to ensure that your views on the proposals are heard
by Hercules and your vote represented at the 2001 Annual Meeting, we urge you to
sign and date the enclosed BLUE Proxy Card and return it to Georgeson
Shareholder Communications Inc. ("Georgeson"), in the enclosed postage paid
envelope TODAY. Execution of the BLUE Proxy Card will not affect your right to
attend the 2001 Annual Meeting and to vote in person.

                  You are eligible to execute a BLUE Proxy only if you owned the
Common Stock on the Record Date. Hercules Board has set March 6, 2001 as the
Record Date for determining those stockholders who will be entitled to notice of
and to vote at the 2001 Annual Meeting. You will retain the right to execute a
proxy card in connection with this proxy solicitation even if you sell your
shares after the Record Date. Accordingly, it is important that you vote the
Shares held by you on the Record Date, or grant a proxy to vote such Shares on
the BLUE proxy card, even if you sell such shares after the Record Date.



                                       28


                  As of the close of business on the Record Date, we believe
that there were 108,115,824 shares of common stock of Hercules issued and
outstanding and entitled to vote. Stockholders will have one vote for each share
of common stock they own with respect to all matters to be considered at the
2001 Annual Meeting.

                  In order for your views on the above-described proposals to be
represented at the 2001 Annual Meeting, please sign and date the enclosed BLUE
proxy card and return it to Georgeson in the enclosed prepaid envelope TODAY.
Execution of the BLUE proxy card will not affect your right to attend the 2001
Annual Meeting and to vote in person. Any proxy may be revoked at any time prior
to the 2001 Annual Meeting by delivering a written notice of revocation or a
later dated proxy for the 2001 Annual Meeting to Georgeson or the Secretary of
Hercules, or by voting in person at the 2001 Annual Meeting. Only your latest
dated proxy will count.

                  Unless otherwise indicated, the BLUE Proxy authorizes the
persons named in the proxy to vote, and such persons will vote, properly
executed and duly returned proxies FOR the ISP nominees. If no marking is made
on your BLUE Proxy with respect to the ratification of the appointment of
Hercules' independent auditors, you will be deemed to have given a direction to
abstain from voting on such matter.

                                  VOTE REQUIRED

                  Based on currently available public information, a quorum will
exist at the 2001 Annual Meeting if holders of not less than a majority of the
shares of Hercules common stock outstanding and entitled to vote at the 2001
Annual Meeting are present in person or by proxy. If a quorum is present, the
election of directors requires the following vote:

o    ELECTION OF DIRECTORS: Hercules claims that its Bylaws require that in
     order to be elected, nominees for director must receive the affirmative
     vote of a majority of all outstanding shares. We disagree with its
     interpretation and believe, based on the reasons set forth below, that
     under Delaware law our nominees should be elected if they receive the
     greatest number of votes cast at the 2001 Annual Meeting.

                  Our view that, under Delaware law and the Hercules Bylaws, our
nominees should be deemed elected if they receive the greatest number of votes
cast at the 2001 Annual Meeting is supported by the following legal analysis:

                  Section 216(3) of the Delaware General Corporation Law
provides that in the absence of specification in the certificate of
incorporation or bylaws of a corporation, "[d]irectors shall be elected by a
plurality of the votes of the shares present in person or represented by proxy
at the meeting and entitled to vote on the election of directors." Delaware case
law has established that in order to overcome this voting rule, the certificate
of incorporation or bylaw provision must "not be couched in ambiguous language,
rather the language employed must be positive, explicit, clear and readily
understandable and susceptible to but one reasonable interpretation, which would


                                       29


indicate beyond doubt that the rule was intended to be abrogated." Standard
Power and Light Corp. v. Investment Associates, Del. Supr., 51 A.2d 572 (1947).

                  Article II, Section 2 of Hercules Bylaws currently provides
that "[a]t each annual meeting, there shall be elected by ballot, by the
majority vote of the stock then issued and outstanding and entitled to vote
thereat, the number of directors necessary to fill the class of those whose term
then expires." The subordinate clause "by the majority vote of the stock then
issued and outstanding and entitled to vote thereat", we believe, should not be
interpreted as requiring that the winner obtain the affirmative vote of the
holders of a majority of the shares issued and outstanding. Such an
interpretation of the subordinate clause is disfavored because it deviates from
the "fundamental principle of majority rule." Centaur Partners, IV v. National
Intergroup, Inc., Del. Supr., 582 A.2d 923, 927 (1990). It also creates a
conflict with the rest of the sentence. Absent the subordinate clause, the
remainder of the sentence requires that a class of directors "shall be elected"
at the annual meeting. A construction that would require the winner to obtain
the affirmative vote of the holders of a majority of the shares issued and
outstanding, we believe, creates the possibility that in a contested election no
candidate will obtain the requisite number of votes, in which event no
successors would be elected at the annual meeting as the By-laws require and the
incumbent directors would continue to hold their seats even though their
three-year terms have expired and indeed, even though the incumbent directors
had received fewer votes than the other candidates or even no votes at all.

                  The Delaware Supreme Court has interpreted a similar bylaw in
a manner that avoids this same problem. In Standard Power, the Court was asked
to interpret the following provision in a certificate of incorporation:

         The holders of the Common Stock Series B shall have the right by the
         vote of a majority in number of shares of the Common Stock Series B
         issued and outstanding to elect a minority in number of the full Board
         of Directors of the corporation, such minority to consist of the
         largest number of Directors which will constitute a minority in number
         of such full Board of Directors, and the directors so elected shall be
         known as Class B directors.

The Court declined to interpret the highlighted phrase as requiring a contestant
to obtain the votes of a majority of the outstanding shares because that result
"would be inequitable, unusual and such as reasonable men would not likely
intend." Id. at 577. The Court ruled that the provision "should be construed to
mean that a majority in number of the issued and outstanding Series B shares
must be voted, and that this is the full extent of the charter requirement in
this regard." Id. At 578. The court accepted that construction even though a
separate provision in the certificate of incorporation "requir[ed] the presence
for quorum purposes of a majority in number of the shares of the Series B stock
before the stockholders are entitled to vote for the election of Class B
directors[.]" Id. At 577.

                  The clause "by the majority vote of the stock then issued and
outstanding and entitled to vote thereat", we believe, should be interpreted in
identical fashion as the phrase from Standard Power: "by the vote of a majority


                                       30


in number of shares of the Common Stock Series B issued and outstanding." The
reasons for our interpretation include the following:

        o       The language of the Hercules Bylaw closely tracks the language
                of the bylaw interpreted in Standard Power.

        o       The Standard Power construction avoids the policy problems of
                holdover directors and the possible disenfranchisement of a
                plurality or even majority of those voting. These policy
                considerations are of particular concern in this case, because
                Hercules has a classified board.

        o       The Standard Power construction avoids creating an internal
                inconsistency in Article II, Section 2.

        o       The language of Article II, Section 2 does not track the clear
                language of Article I, Section 6: "the affirmative vote of the
                holders of a majority of the shares present in person or by
                proxy." If the drafters of the Bylaws wanted to deviate from the
                default rule in Article I, Section 6, they knew how to clearly
                draft such language (e.g., "election of a new director shall
                require the affirmative vote of the holders of a majority of the
                shares issued and outstanding").

                  Furthermore, the interpretation by the Company is not
consistent with the scheme of Section 141(d) of the Delaware General Corporation
Law, which establishes the conditions for a classified board of directors. The
statute permits, by the certificate of incorporation or a by-law adopted by the
vote of the stockholders, division of the directors into one, two or three
classes. The term of the first class shall expire at the next annual meeting,
the second class the year thereafter and the third class two years thereafter.
The statute further provides "... and at each annual election held after such
classification and election, directors shall be chosen for a full term, as the
case may be, to succeed those whose terms expired." Should the Company's
interpretation be adopted and a class of directors not be elected in a
particular year, the incumbent directors would remain in office since their
successors would not be elected and qualified. We believe that this result,
which should be impermissible in any event as a matter of good corporate
governance, also runs contrary to New York Stock Exchange policy, as Section
304.00 of the NYSE Listed Company Manual specifies that "... directors' terms of
office should not exceed three years." There are no mechanics in the By-laws to
establish how many classes of directors would be elected in the second year and
third year and the term of each class. While this is also true should a
plurality not elect the new members of the class, the higher voting requirement
makes this a greater likelihood, particularly in the case of a proxy contest.

                  Our proxy statement and a form of proxy will be delivered to
holders of at least the percentage of the Company's common stock required under
applicable law to carry the Proposals.



                                       31


                         WE STRONGLY RECOMMEND THAT YOU
                    VOTE "FOR" THE ELECTION OF OUR NOMINEES.

                            METHOD OF COUNTING VOTES

                  The holders of not less than a majority of the number of
shares of Hercules common stock outstanding and entitled to vote at the 2001
Annual Meeting must be represented in person or by proxy in order to constitute
a quorum for the transaction of business. Abstentions and broker non-votes will
be included for purposes of determining whether a quorum exists. Broker
non-votes occur when brokers do not receive voting instructions from their
customers on non-routine matters and consequently have no discretion to vote on
those matters. If your Hercules shares are held in the name of a brokerage firm,
bank nominee or other institution, you should contact the person responsible for
your account and give instructions for a proxy card to be issued so that your
shares will be represented at the 2001 Annual Meeting.

                  After a quorum is determined to exist at the 2001 Annual
Meeting, under our interpretation of Hercules director election Bylaw,
abstentions and broker non-votes will have no effect on the outcome of the
election of directors. Under Hercules' interpretation of that Bylaw, however,
abstentions and broker non-votes will be counted as votes cast against the
election of directors.

                             ADDITIONAL INFORMATION

                  The principal executive offices of Hercules Incorporated are
at Hercules Plaza, 1313 North Market Street, Wilmington, Delaware 19894.
Hercules manufactures chemical specialties used in a variety of home, office and
industrial products including process paper chemicals, water treatment
chemicals, water-soluble polymers, food ingredients, resins and polypropylene
and polyethylene fibers. Hercules' primary markets include pulp and paper,
petroleum refineries, food processors and manufacturers, construction materials,
adhesives, pharmaceutical companies and personal care product manufacturers.
Except as otherwise noted herein, the information concerning Hercules has been
taken from or is based upon documents and records on file with the SEC and other
publicly available information. Although we do not have any knowledge that would
indicate that any statement contained herein based upon such documents and
records is untrue, we do not take any responsibility for the accuracy or
completeness of the information contained in such documents and records, or for
any failure by Hercules to disclose events that may affect the significance or
accuracy of such information.

                  The principal executive offices of ISP are at 300 Delaware
Avenue, Wilmington, Delaware 19801. We are a manufacturer of specialty chemicals
and mineral products.

                  We are subject to the informational requirements of the
Exchange Act, and, in accordance with the Exchange Act, file reports, proxy
statements and other documents with the SEC relating to our business, financial
condition and other matters. These reports, proxy statements and other documents
can be inspected and copied at the public reference facilities of the SEC at 450


                                       32


Fifth Street, N.W., Washington, DC 20549, and at the regional offices of the SEC
located at Seven World Trade Center, 13th Floor, New York, New York 10048 and
Citicorp Center, 500 West Madison Street, Suite 1400, Chicago, Illinois 60661.
Copies of ISP's filings with the SEC can also be obtained by mail for a fee by
writing to the SEC's principal office at 450 Fifth Street, N.W., Washington, DC
20549. You can also get electronic copies of our filings with the SEC for free
on the SEC's Internet web site at http://www.sec.gov. Copies of our filings with
the SEC are also be available for inspection at the offices of the New York
Stock Exchange, 20 Broad Street, New York, New York 10005.

                          PROXY SOLICITATION; EXPENSES

                  Executed proxies may be solicited in person, by mail,
advertisement, telephone, telecopier, telegraph or similar means. Solicitation
may be made by directors, officers, investor relations personnel and other
employees of ISP and their affiliates, none of whom will receive additional
compensation for such solicitation. Proxies will be solicited from individuals,
brokers, banks, bank nominees and other institutional holders. We have requested
banks, brokerage houses and other custodians, nominees and fiduciaries to
forward all solicitation materials to the beneficial owners of the shares they
hold of record. We will reimburse these record holders for their reasonable
out-of-pocket expenses.

                  In addition, ISP has retained Georgeson to solicit proxies on
our behalf in connection with the 2001 Annual Meeting. Georgeson will employ
approximately [75] people in its efforts. We have agreed to reimburse Georgeson
for its reasonable expenses and to pay to Georgeson fees not to exceed $225,000.

                  The entire expense of our proxy solicitation is being borne by
ISP. In the event that our nominees are elected to Hercules Board, we may seek
reimbursement of such expenses from Hercules. ISP does not intend to seek
reimbursement for the stipend it pays to its nominees and does not intend to
seek stockholder approval of reimbursement of its other expenses. In addition to
the engagement of Georgeson described above, costs related to the solicitation
of proxies include expenditures for printing, postage, legal and related
expenses and are expected to be approximately $__________. Total payment of
costs to date in furtherance of our proxy solicitation is approximately
$_________.

                 CERTAIN INFORMATION CONCERNING THE PARTICIPANTS

                  ISP, our nominees for directorships and the following officers
of ISP may be deemed to be "participants" (as defined in Instruction 3 to Item 4
of Rule 14a-101 of the Exchange Act) in this proxy solicitation: Richard A.
Weinberg, Executive Vice President, General Counsel and Secretary; Randall R.
Lay, Executive Vice President and Chief Financial Officer; Susan B. Yoss,
Executive Vice President and Treasurer; Stephen R. Olsen, Senior Vice
President-Corporate Development; Jared Landaw, Vice President-Law; and Ben
Stoller, Director-Corporate Finance and Investments. Information relating to the
beneficial ownership of common stock of Hercules by the participants in this


                                       33


solicitation and certain other information relating to the participants is
contained in Annex V to this proxy statement and is incorporated in this proxy
statement by reference. Except as set forth in Annex V, none of the participants
in this solicitation are party to any commercial dealings with Hercules or its
subsidiaries required to be discussed pursuant to Schedule 14A promulgated under
the Exchange Act, which governs the disclosure contained in this proxy
statement.

                     CERTAIN INTERESTS IN THE PROPOSALS AND
                     WITH RESPECT TO SECURITIES OF HERCULES

                  To the knowledge of ISP, there are no contracts, arrangements,
understandings or relationships (legal or otherwise) among ISP or its associates
with respect to any securities of Hercules.

                  Gloria Schaffer and Raymond Troubh, each in his or her
capacity as a nominee for election to the Hercules Board, will receive a stipend
of $25,000 from ISP for his or her service as a nominee. This stipend is not
refundable in any manner in connection with the outcome of our proxy
solicitation or otherwise. The Nominees are each party to an indemnity agreement
with ISP (the "Director Indemnity Agreements"). In accordance with the terms of
the Director Indemnity Agreements, ISP has agreed to indemnify and hold harmless
each of the nominees from and against, among other things, all expenses,
liabilities and losses, including reasonable attorney's fees, related to any
action, suit or proceeding to which such nominee is made a party or threatened
to be made a party by reason of such nominee's action or inaction while serving
as a nominee.





                                       34


                         SECURITY OWNERSHIP OF DIRECTORS
                           AND MANAGEMENT OF HERCULES

                  The following table presents, as of March 6, 2001, based
solely on information contained in Hercules' 2001 proxy statement, the common
stock beneficially owned (as that term is defined by the SEC) by all directors
and named executive officers of Hercules, and the directors and executive
officers of Hercules as a group.

                  Except as otherwise noted in a footnote below, each director,
nominee and executive officer has sole voting and investment power with respect
to the number of shares of common stock set forth opposite his or her name in
the table.


                                               Shares          Options
                                            Beneficially      Exercisable       Restricted      Percent of
                  Name                        Owned (1)      Within 60 Days    Stock Units        Shares
------------------------------------------ ---------------- ----------------- --------------- ---------------
                                                                                         
DIRECTORS AND OFFICERS
Thomas L. Gossage, Director and
Officer (2)                                    129,003          264,000               0              *
J. Barry, Officer                               71,954            7,200               0              *
D. W. DiDonna, Officer                          44,637          148,100               0              *
J. G. Drosdick, Director                         9,423            6,000           1,100              *
R. M. Fairbanks, III, Director                  12,088           21,000           1,253              *
I. J. Floyd, Officer                            65,944           71,800               0              *
A. R. Hirsig, Director                           6,554            6,000           1,100              *
E. E. Holiday, Director                          3,999           18,000           1,376              *
R. G. Jahn, Director                            14,236           27,000               0              *
G. N. Kelley, Director                           9,744           27,000           2,185              *
R. L. MacDonald, Jr., Director                  15,421           27,000           1,928              *
G. MacKenzie, Officer                          125,997          170,280           1,299              *
H. E. McBrayer, Director                        77,324           24,000           1,527              *
P. McCausland, Director                          7,784            9,000           1,100              *
J. A. H. Shober, Director                        5,250            6,000           1,100              *
P. A. Sneed, Director                           11,925           18,000           1,253              *
V. J. Corbo, Director and Officer (3)          109,119          275,200               0              *
H. J. Tucci, Officer (4)                        53,231          209,200               0              *
ALL DIRECTORS AND OFFICERS
AS A GROUP                                     773,633        1,448,520          15,221              2%

*      Less than 1% of Hercules' outstanding shares of common stock.

(1)    Includes shares, as of December 31, 2000, in the Savings and Investment
       Plan as follows: J. Barry, 2,351; D. W. DiDonna, 1,276; I. J. Floyd,
       1,372; and G. MacKenzie, 3,421; and all directors and officers as a
       group, 8,420. Includes shares with restrictions and forfeiture risks as
       specified under the Long-Term Incentive Compensation Plan: T. L. Gossage,
       128,003; J. Barry, 38,000; D. W. DiDonna, 39,747; G. MacKenzie, 76,270;
       I. J. Floyd, 45,910; H. J. Tucci, 1,821; and all directors and officers
       as a group, 274,956. Owners have the same voting and dividend rights as
       other shareholders of Hercules, except for the right to sell or transfer.
       Included in the non-employee directors' totals is a one-time equity
       award. Mr. Kelley's total includes 1,594 shares that he holds jointly
       with his spouse.

(2)    Named Chairman and Chief Executive Officer on October 17, 2000.


                                       35


(3)    Resigned as President, Chairman and Chief Executive Officer on October
       17, 2000.

(4)    Retired as officer on December 1, 2000.
















                                       36


                       PRINCIPAL STOCKHOLDERS OF HERCULES

                  The following table sets forth, based solely, except as
otherwise described herein, on information contained in Hercules' 2001 proxy
statement, the number and percentage of outstanding shares of common stock
beneficially owned by each person known to ISP as of such date to be the
beneficial owner of more than five percent of the outstanding shares of common
stock.


                                                                 Shares
                                                              Beneficially               Percent of
                        Name                                     Owned                     Shares
------------------------------------------------------ --------------------------- ------------------------
                                                                                 
5% SHAREHOLDERS
International Specialty Products, Inc.                   10,719,200                    9.9%(1)
ISP Investments Inc.
ISP Opco Holdings Inc.
c/o ISP Management Company, Inc.
1361 Alps Road
Wayne, New Jersey  07670

T. Rowe Price Associates, Inc. (2)
100 E. Pratt Street
Baltimore, Maryland  21202                                7,198,428                    6.7%

Mario J. Gabelli and related                              6,707,400                    6.23%
entities (3)
c/o Gabelli Asset Management Inc.
One Corporate Center
Rye, New York  10580


(1)  ISP Investments Inc. (through ISP Investments Grantor Trust) has the sole
     power to vote, direct the voting of, dispose of and direct the disposition
     of the shares. ISP Opco Holdings Inc., by virtue of its indirect ownership
     of all of the outstanding capital stock of ISP Investments Inc., may be
     deemed to own beneficially (solely for purposes of Rule 13d-3) the shares.
     ISP, by virtue of its ownership of all of the outstanding common stock of
     ISP Opco Holdings Inc., may be deemed to own beneficially (solely for
     purposes of Rule 13d-3) the shares. Samuel J. Heyman, by virtue of his
     beneficial ownership (as defined in Rule 13d-3) of approximately 79% of the
     capital stock of ISP, may be deemed to own beneficially (solely for
     purposes of Rule 13d-3) the shares.

(2)  Share holding as of March 6, 2001, as reported on Schedule 13G most
     recently filed by such shareholder.

(3)  Share holding as of March 6, 2001, as reported on Amendment No. 1 to the
     Schedule 13D filed by such shareholder.




                                       37


              STOCKHOLDERS' PROPOSALS IN HERCULES' PROXY STATEMENT

                  Pursuant to Rule 14a-8(e)(2) under the Exchange Act, any
proposal by a stockholder at the 2001 Annual Meeting, to be included in
Hercules' proxy statement, must be received in writing at Hercules' principal
executive offices not less than 120 calendar days in advance of the date of
Hercules' proxy statement released to security holders in connection with its
2000 Annual Meeting of Stockholders. However, if the date of the meeting is
changed by more than 30 days from the date of the previous year's meeting, then
the deadline is a reasonable time before Hercules begins to print and mail its
proxy materials.

                  Proposals should be addressed to the Corporate Secretary,
Hercules Incorporated, Hercules Plaza, 1313 North Market Street, Wilmington,
Delaware 19894.

WE URGE YOU TO SIGN, DATE AND RETURN THE BLUE PROXY CARD IN FAVOR OF THE
ELECTION OF OUR NOMINEES DESCRIBED IN THIS PROXY STATEMENT.

Dated:  __________ __, 2001

                                       Sincerely,

                                       Your Fellow Stockholder:

                                       INTERNATIONAL SPECIALTY PRODUCTS INC.






                                       38


                                                                         ANNEX I

                 INFORMATION CONCERNING INTERNATIONAL SPECIALTY
                      PRODUCTS INC. AND OTHER PARTICIPANTS
                               IN THE SOLICITATION

                  Information is being given herein for (i) International
Specialty Products Inc., a Delaware corporation ("ISP"), (ii) Samuel J. Heyman,
a natural person and nominee for the Board of Directors of the Company, (iii)
Sunil Kumar, a natural person and nominee for the Board of Directors of the
Company, (iv) Gloria Schaffer, a natural person and nominee for the Board of
Directors of the Company, (v) Raymond Troubh, a natural person and nominee for
the Board of Directors of the Company, (vi) Richard A Weinberg, Executive Vice
President, General Counsel and Secretary of ISP ("Weinberg"), (vii) Randall R.
Lay, Executive Vice President and Chief Financial Officer of ISP ("Lay"), (viii)
Susan B. Yoss, Executive Vice President and Treasurer of ISP ("Yoss"), (ix)
Stephen R. Olsen, Senior Vice President-Corporate Development of ISP ("Olsen"),
(x) Jared Landaw, Vice President-Law of ISP ("Landaw") and (xi) Ben Stoller,
Director-Corporate Finance and Investments of ISP ("Stoller" and together with
Weinberg, Lay, Yoss, Olsen and Landaw, the "ISP Participants"), who are each a
"participant in a solicitation" as defined under the proxy rules (collectively,
the "Participants").

                  Information is also given for each of the entities listed on
Schedule A to this Annex V, each of which is an "associate", as defined under
the proxy rules, of ISP.

                  ISP is a Delaware corporation. ISP has its principal place of
business at 300 Delaware Avenue, Wilmington, Delaware 19801. The business
address of each of the ISP Participants is c/o ISP Management Company, Inc.,
1361 Alps Road, Wayne, New Jersey 07470. The address of each of the entities
listed on Schedule A to this Annex VI is c/o ISP Management Company, Inc., 1361
Alps Road, Wayne, New Jersey 07470.

                  The Participants may be deemed to have beneficial ownership of
Hercules Common Stock as set forth immediately below. Except as set forth below,
no associates of any of the Participants owns any Hercules Common Stock.




                                     A-I-1




                                              NUMBER OF SHARES                     APPROXIMATE MARGIN
                                                 OF HERCULES                    INDEBTEDNESS WITH RESPECT
NAME                                            COMMON STOCK                         TO COMMON STOCK
----                                            ------------                         ---------------
                                                                                     
ISP Investments Inc.                             10,719,200                                (2)
                                             (direct ownership)(1)
ISP Opco Holdings Inc.                           10,719,200                                (2)
                                           (indirect ownership)(1)
International Specialty Products                 10,719,200                                (2)
Inc.                                       (indirect ownership)(1)
Samuel J. Heyman                                 10,719,200                                (2)
                                           (indirect ownership)(1)
Sunil Kumar                                           0                                    $ 0
Gloria Schaffer                                       0                                    $ 0
Raymond Troubh                                        0                                    $ 0
Richard A. Weinberg                                   0                                    $ 0
Randall R. Lay                                        0                                    $ 0
Susan B. Yoss                                         0                                    $ 0
Stephen R. Olsen                                      0                                    $ 0
Jared Landaw                                          0                                    $ 0
Ben Stoller                                           0                                    $ 0


(1)      ISP Investments (through ISP Investments Grantor Trust) has the sole
         power to vote, direct the voting of, dispose of and direct the
         disposition of the Hercules Common Stock. ISP Opco Holdings Inc. ("ISP
         Opco"), by virtue of its indirect ownership of all of the outstanding
         capital stock of ISP Investments, may be deemed to own beneficially
         (solely for purposes of Rule 13d-3) the Hercules Common Stock owned by
         ISP Investments. International Specialty Products Inc. ("ISP"), by
         virtue of its ownership of all of the outstanding common stock of ISP
         Opco, may be deemed to own beneficially (solely for purposes of Rule
         13d-3) the Hercules Common Stock owned by ISP Investments. Mr. Heyman,
         by virtue of his beneficial ownership (as defined in Rule 13d-3) of
         approximately 79% of the capital stock of ISP, may be deemed to own
         beneficially (solely for purposes of Rule 13d-3) the Hercules Common
         Stock owned by ISP Investments.

(2)      In the ordinary course of its business, ISP Investments Inc. purchases
         securities for its investment portfolio with funds obtained from the
         working capital of ISP Investments, loans from affiliates and
         borrowings pursuant to standard margin arrangements. Because the
         securities from multiple investments are pooled in one account, the
         amount of margin indebtedness incurred by ISP in connection with its


                                     A-I-2


         purchases of Hercules Common Stock, which purchases were numerous and
         made over several months, is impossible to determine with any degree of
         certainty.

                  To the best of the knowledge of the Participants and their
associates, none has been, within the past year, a party to any contract,
arrangement or understanding with any person with respect to any securities of
Hercules, including but not limited to joint ventures, loan or option
arrangements, puts or calls, guarantees against loss or guarantees of profits,
division of losses or profits, or the giving or withholding of proxies.

                  No Participant or associate owns any securities of the Company
of record but not beneficially.

                  ISP does not have any special arrangements with any of the ISP
Participants in connection with this proxy solicitation.

                  None of the Participants and none of their associates has any
arrangement or understanding with any person with respect to (i) any future
employment with Hercules or (ii) any future transactions to which Hercules or
any of its affiliates may be a party. ISP and certain of its subsidiaries
purchase and sell certain chemical products to Hercules and/or certain
subsidiaries or affiliates of Hercules in the ordinary course of business in an
aggregate amount per year that does not exceed $500,000. No family relationships
exist among the Participants' nominees or between any Hercules director or
executive officer and any of the Participants' nominees.

                  The following is a summary of all transactions in Hercules
securities by the Participants over the last two years.

       DATE OF TRANSACTION     NATURE OF TRANSACTION       NUMBER OF SHARES
-------------------------------------------------------------------------------
          01/28/00                      Buy                    21,700
          03/01/00                      Buy                   196,000
          03/02/00                      Buy                 1,030,000
          03/03/00                      Buy                 1,200,000
          03/09/00                      Buy                    60,000
          03/13/00                      Buy                    35,000
          03/14/00                      Buy                    11,800
          03/15/00                      Buy                    45,000
          03/20/00                      Buy                   150,000
          03/22/00                      Buy                    65,000
          03/23/00                      Buy                    13,000
          03/28/00                      Buy                   200,000
          03/29/00                      Buy                   106,000
          03/31/00                      Buy                    55,000
          04/03/00                      Buy                    35,000
          04/04/00                      Buy                    62,600


                                     A-I-3


       DATE OF TRANSACTION     NATURE OF TRANSACTION       NUMBER OF SHARES
-------------------------------------------------------------------------------
          04/07/00                      Buy                     2,500
          04/10/00                      Buy                   102,000
          04/12/00                      Buy                   151,000
          04/13/00                      Buy                   165,500
          04/14/00                      Buy                   102,000
          04/17/00                      Buy                    55,000
          04/18/00                      Buy                    63,000
          04/19/00                      Buy                    60,000
          04/20/00                      Buy                   370,000
          04/24/00                      Buy                    34,900
          04/25/00                      Buy                   100,000
          04/26/00                      Buy                    81,500
          04/28/00                      Buy                     7,500
          05/01/00                      Buy                       200
          05/02/00                      Buy                    35,000
          05/03/00                      Buy                   135,000
          05/04/00                      Buy                    95,000
          05/05/00                      Buy                    50,000
          05/08/00                      Buy                    35,000
          05/09/00                      Buy                    35,000
          05/10/00                      Buy                     1,000
           6/5/00                       Buy                    14,100
           6/6/00                       Buy                    41,200
           6/7/00                       Buy                    35,000
           6/8/00                       Buy                    14,400
           6/9/00                       Buy                    16,000
          6/19/00                       Buy                    70,000
          6/20/00                       Buy                    50,000
          6/22/00                       Buy                     2,500
          6/23/00                       Buy                    25,000
          7/10/00                       Buy                    35,000
          7/11/00                       Buy                    35,000
          7/12/00                       Buy                    11,800
          7/14/00                       Buy                 5,355,000
          7/17/00                       Buy                    40,000
          7/20/00                       Buy                     3,000
          7/21/00                       Buy                     4,000


                                     A-I-4


                                                           SCHEDULE A TO ANNEX I


               Associates of International Specialty Products Inc.
               ---------------------------------------------------


ISP Acquisition Corp.
ISP Investments Inc.
ISP Opco Holdings Inc.
Belleville Realty Corp.
ISP Alginates Inc.
ISP Management Company, Inc.
ISP Chemicals Inc.
ISP Minerals Inc.
ISP Technologies Inc.
ISP Mineral Products Inc.
ISP Environmental Services Inc.
Bluehall Incorporated
ISP Realty Corporation
ISP Real Estate Company, Inc.
International Specialty Products Funding Corporation
ISP Newark Inc.
ISP Van Dyk Inc.
ISP Fine Chemicals Inc.
ISP Freetown Fine Chemicals Inc.
Verona Inc.
ISP Global Technologies Inc.
ISP International Corp.
ISP Marl Holdings GmbH
ISP Holdings (U.K.) Ltd.
ISP Ireland
ISP (Puerto Rico) Inc.
ISP Marl GmbH
ISP Acetylene GmbH
ISP Alginates (U.K.) Ltd.
ISP (Great Britain) Co. Ltd.
ISP Andina, C.A.
ISP Argentina S.A.
ISP Asia Pacific Pte Ltd.
ISP (Australasia) Pte Ltd.
ISP (Belgium) N.V.
ISP (Belgium) International N.V.
ISP do Brasil Ltda.
ISP (Canada) Inc.
ISP Ceska Republika Spol S.R.O.


                                     A-I-5



ISP (China) Limited
ISP Colombia Ltda.
ISP Freight Service N.V.
ISP Global Operations (Barbados) Inc.
ISP Global Technologies (Germany) Holding GmbH
ISP Customer Service GmbH ISP Global Technologies Deutschland GmbH International
Specialty Products ISP (France) S.A. ISP (Hong Kong) Limited ISP (Italia) S.r.l.
ISP (Japan) Ltd.
ISP (Korea) Limited
ISP Mexico, S.A. de C.V.
ISP (Norden) A.B.
ISP (Osterreich) GmbH
ISP (Polska) Sp.z. o.p.
ISP Sales (Barbados) Inc.
ISP Sales (U.K.) Limited
ISP (Singapore) Pte Ltd.
ISP (Switzerland) A.G.
ISP (Thailand) Co., Ltd.
Chemfields Pharmaceuticals Private Limited
Kelp Industries Pty Ltd
Arramara Teoranta
Thorverk Hf



                                     A-I-6


                               [PRELIMINARY COPY]

PROXY

                              HERCULES INCORPORATED

              PROXY SOLICITED ON BEHALF OF INTERNATIONAL SPECIALTY
           PRODUCTS INC. AND THE OTHER PARTICIPANTS IDENTIFIED IN THE
               PROXY STATEMENT FURNISHED HEREWITH ("ISP") FOR THE
                    ANNUAL MEETING OF STOCKHOLDERS, APRIL 26,
                               2001 AT 11:00 A.M.

The undersigned stockholder of Hercules Incorporated ("Hercules") hereby
appoints Samuel J. Heyman and Sunil Kumar and each of them, as attorneys and
proxies, each with power of substitution and revocation, to represent the
undersigned at the Annual Meeting of Stockholders of Hercules Incorporated to be
held at the Delaware Art Museum, 2301 Kentmere Parkway, Wilmington, Delaware on
April 26, 2001 at 11:00 A.M., local time, and at any adjournment or postponement
thereof, with authority to vote all shares held or owned by the undersigned in
accordance with the directions indicated herein.

                  Receipt of the Proxy Statement furnished herewith is hereby
acknowledged.

THIS PROXY WHEN PROPERLY EXECUTED WILL BE VOTED IN THE MANNER DIRECTED BY THE
UNDERSIGNED STOCKHOLDER. ON MATTERS FOR WHICH YOU DO NOT SPECIFY A CHOICE, YOUR
SHARES WILL BE VOTED IN ACCORDANCE WITH THE RECOMMENDATION OF ISP. YOU MAY
APPROVE OR VOTE SEPARATELY ON ANY OR ALL OF THE PROPOSALS.





                (CONTINUED AND TO BE SIGNED ON THE REVERSE SIDE)








             ISP RECOMMENDS A VOTE "FOR" THE NOMINEES LISTED BELOW.
                                       ---



           Election of Directors


                                                                 
FOR all nominees listed on the right     WITHHOLD AUTHORITY to vote    NOMINEES: Samuel J. Heyman, Sunil Kumar, Gloria
(except as marked to the contrary        for all nominees listed to    Schaffer, Raymond Troubh
hereon).                                 the right.                    (Instructions:  To withhold authority to vote for
                                                                       any individual nominee, write that nominee's name in
               [_]                                   [_]               the space provided below.)

                                                                       ----------------------------------------------------


                         ISP MAKES NO RECOMMENDATION ON
                       THE FOLLOWING MATTER TO BE VOTED ON
                           AT THE 2001 ANNUAL MEETING


                                                                          FOR           AGAINST         ABSTAIN
RATIFICATION OF INDEPENDENT AUDITORS                                      [_]             [_]             [_]







IN THEIR DISCRETION, THE PROXIES ARE AUTHORIZED TO VOTE UPON SUCH OTHER BUSINESS
AS MAY PROPERLY BE PRESENTED TO THE MEETING OR ANY ADJOURNMENT OR POSTPONEMENT
THEREOF.



P             Dated: _____________, 2001


R             -----------------------------------------
                       (Signature)

O
              -----------------------------------------
                       (Signature if held jointly)
X
              -----------------------------------------
              Title:
Y

              Please sign exactly as name appears hereon. When shares are held
              by joint tenants, both should sign. When signing as attorney,
              executor, administrator, trustee, or guardian, please give full
              title as such. If a corporation, please sign in full corporate
              name by president or other authorized officer. If a partnership,
              please sign in partnership name by authorized person. The signer
              hereby revokes all proxies heretofore given by the signer to vote
              at the 2001 Annual Meeting of Hercules Incorporated and any
              adjournment or postponement thereof.