or Mesolabium, a mathematical instrument invented by the ancients, for finding two mean

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(A) We have taken this article from the Biographical Dictionary; the editors of which took it from the life of Meninski prefixed to the new edition of his great work. mean proportions mechanically, which they could not perform geometrically. It consists of three parallelograms, moving in a groove to certain intersections. Its figure is described by Euclidius, in his Commentary on Archimedes. See also Pappus, lib. 3.