What is a sudden encounter; a collision; a shock; -- said of things. [Obs.] From these laws may be deduced the rules of the congresses and reflections of two bodies. Cheyne called?

congress — A sudden encounter; a collision; a shock; -- said of things. [Obs.] From these laws may be deduced the rules of the congresses and reflections of two bodies. Cheyne. (Webster's 1913.)

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