What is a weight sufficient to balance another, as in the opposite scale of a balance; an equal weight. Fastening that to our exact balance, we put a metalline counterpoise into the opposite scale. Boyle called?

counterpoise — A weight sufficient to balance another, as in the opposite scale of a balance; an equal weight. Fastening that to our exact balance, we put a metalline counterpoise into the opposite scale. Boyle. (Webster's 1913.)

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