<ARTICLE> 5
<LEGEND>
THIS SCHEDULE CONTAINS SUMMARY FINANCIAL INFORMATION EXTRACTED FROM HERCULES
INCORPORATED'S CONSOLIDATED BALANCE SHEETS AND CONSOLIDATED STATEMENTS OF INCOME
AND IS QUALIFIED IN ITS ENTIRETY BY REFERENCE TO SUCH FINANCIAL STATEMENTS.
</LEGEND>
<MULTIPLIER> 1,000

                             
<PERIOD-TYPE>                   9-MOS
<FISCAL-YEAR-END>                          DEC-31-1999
<PERIOD-END>                               SEP-30-1999
<CASH>                                          88,000
<SECURITIES>                                         0
<RECEIVABLES>                                  630,000
<ALLOWANCES>                                    16,000
<INVENTORY>                                    398,000
<CURRENT-ASSETS>                             1,328,000
<PP&E>                                       2,939,000
<DEPRECIATION>                               1,628,000
<TOTAL-ASSETS>                               5,908,000
<CURRENT-LIABILITIES>                        1,118,000
<BONDS>                                              0
<PREFERRED-MANDATORY>                                0
<PREFERRED>                                          0
<COMMON>                                        83,000
<OTHER-SE>                                     774,000
<TOTAL-LIABILITY-AND-EQUITY>                 5,908,000
<SALES>                                      2,421,000
<TOTAL-REVENUES>                             2,421,000
<CGS>                                        1,308,000
<TOTAL-COSTS>                                  714,000
<OTHER-EXPENSES>                                     0
<LOSS-PROVISION>                                     0
<INTEREST-EXPENSE>                             145,000
<INCOME-PRETAX>                                227,000
<INCOME-TAX>                                    76,000
<INCOME-CONTINUING>                            151,000
<DISCONTINUED>                                       0
<EXTRAORDINARY>                                      0
<CHANGES>                                            0
<NET-INCOME>                                   151,000
<EPS-BASIC>                                       1.48
<EPS-DILUTED>                                     1.47