WILMINGTON, DE, APRIL 3, 2008 . . . Hercules Incorporated (NYSE: HPC) today announced the following schedule and teleconference information for its first quarter earnings release and teleconference:

Earnings Release: April 21, 2008 – After the stock market closes.

Distribution: Business Wire and Hercules' website at www.herc.com.

Teleconference: April 22, 2008 — 8:00 a.m. (Eastern).

Dial in Number: 973-935-8511 – Ask for Conference ID # 42401160
Please call 5-10 minutes before the scheduled start of the teleconference.

Webcast: Listen-only mode via Internet broadcast from Hercules' website at www.herc.com, under Shareholder Information.

Web Replay: Will be available beginning at noon on April 22, 2008 on the web at www.herc.com, under Shareholder Information.

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