Piezometers are instruments used in studying the compressibility of solids and liquids. The exemplar presented here is a piezometer for liquids of the kind invented in 1822 by Hans Christian Oersted (1777-1851) who used it to measure the compression coefficient of water.
In liquids, for pressures up to tens of atmospheres, contractions are perfectly elastic and miscellaneousations in volume are directly proportional to the initial volumes and the pressures that have produced them, except for a constant of proportionality that measures the compression coefficient.
In 1819, Jacob Perkins revealed and measured the compressibility of water and was the first to call the instruments employed piezometers.
Other physicists, among whom Hans Christian Oersted with his piezometer, confirmed the compressibility of liquids and for some measured the compression coefficient. ...continues