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(36.) It has since been proved, that water, and other liquids, are compressible. In the year 1761, Canton communicated to the Royal Society the results of some experiments which proved this fact. He provided a glass tube with a bulb, such as that described in (ssss1), and filled the bulb and a part of the tube with water well purified from air. He then placed this in an apparatus called a condenser, by which he was enabled to submit the surface of the liquid in the tube to very intense pressure of condensed air. He found that the level of the liquid in the tube fell in a perceptible degree upon the application of the pressure. The same experiment established the fact, that liquids are elastic; for upon removing the pressure, the liquid rose to its original level, and therefore resumed its former dimensions.

(37.) Elasticity does not always accompany compressibility. If lead or iron be submitted to the hammer, it may be hardened and diminished in its volume; but it will not resume its former volume after each stroke of the hammer.