or Elastic Force, that inherent property in bodies by which they recover their original figure after any force which has disturbed it is withdrawn. Elasticity is generally accounted for by the great law of attraction. Thus, when a hard body is struck or bent, so that the component parts are moved a little from each other, but not so far as to overcome the power of the attractive force by which they cohere, they necessarily, on the cessation of that external force, return to their former state. All hard bodies are elastic, as steel, glass, and ivory, and many soft ones, as caoutchouc, silk thread, &c. The great elasticity of air is a familiar fact. Liquids are also perfectly elastic, but in the smallest degree.