A pump consisting of a screw within a cylinder. When the screw is turned, water is moved from one end to the other.

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When Archimedes has sex with his wife.

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When you yell 'eureka' upon ejaculating.

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An ancient invention that can be used in the vagina to evacuate excess menses.
In an incredibly archane reference to an ancient invention, a sexual double entendre is achieved.
by scorpionmintred November 19, 2004
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