This instrument is almost a faithful reproduction of S'Gravesande's apparatus described in his “Physices Elementa Mathematica,” 1742 (but not in the previous editions). It is described or alluded to by few modern writers, except Biot in his “Traité de Physique.” It consists of a strong wooden table or frame, with a vice at each end, between which a wire or lamina may be stretched with a determinate tension by means of a weight attached by a cord, passing over a pulley in the manner of the musical apparatus, called a Monochord. After the tension is adjusted, both vices are screwed fast, the space included between them being exactly 50 inches. If now, any deviation of the middle point of the wire included by the vices be made (similar to the action of sounding a harp-string), the force required to pull it a certain distance aside will depend, 1st, on the length of the wire; 2d, on its tension; 3d, on its extensibility, or the modulus of elasticity.
Propagation of Axisymmetric Stoneley Waves in Elastic Solids
