previous next

Pie-zom′e-ter.

An instrument invented by Oersted for measuring the compressibility of liquids.

It consists of an elongated bulb a having a graduated stem of small bore. The instrument is filled with any liquid up to a certain mark on the stem, and a globule of mercury is placed above the liquid. It is then placed in a cylindrical vessel b filled with water, to which pressure is applied by means of a screw piston. The number of graduations through which the globule of mercury is thus caused to descend indicates the apparent diminution in bulk of the liquid; that is, the excess of its contraction over that of the bulb which contains it. This depends on the quality of the glass of which the bulb is composed; its amount is ascertained and the proper correction is applied by deducting the increase in volume due to the difference of the two expansions, from the indication of the mercurial index; this gives the absolute con traction of the liquid.

Piezometer.

Creative Commons License
This work is licensed under a Creative Commons Attribution-ShareAlike 3.0 United States License.

An XML version of this text is available for download, with the additional restriction that you offer Perseus any modifications you make. Perseus provides credit for all accepted changes, storing new additions in a versioning system.

hide Places (automatically extracted)

View a map of the most frequently mentioned places in this document.

Download Pleiades ancient places geospacial dataset for this text.

hide Display Preferences
Greek Display:
Arabic Display:
View by Default:
Browse Bar: