• WordNet 3.6
    • n hydrometer a measuring instrument for determining the specific gravity of a liquid or solid
    • ***
Webster's Revised Unabridged Dictionary
    • Hydrometer (Physics) An instrument for determining the specific gravities of liquids, and thence the strength spirituous liquors, saline solutions, etc.
    • Hydrometer An instrument, variously constructed, used for measuring the velocity or discharge of water, as in rivers, from reservoirs, etc., and called by various specific names according to its construction or use, as tachometer rheometer hydrometer pendulum, etc.; a current gauge.
    • ***
Century Dictionary and Cyclopedia
    • n hydrometer An instrument for measuring specific gravity, especially that of water and other fluids, and hence the strength of spirituous liquors and of various solutions. In Nicholson's hydrometer for solids (see cut) the weight is first determined which, placed in the upper pan, will depress the instrument to the zero-mark ; then the weights are found which are needed to do this when the body experimented upon is placed, first in the upper and then in the lower pan. The difference between these last weights and that first found gives the weight of the body in air and in water respectively, whence the specific gravity is calculated in the usual manner. The common type of hydrometer for liquids consists of a glass tube with a graduated stem of uniform diameter, a bulb to cause it to float in the liquid, and a weight or counterpoise to cause the stem to stand upright as it floats. From the reading of the scale at the point which is on a level with the surface of the liquid in which it is floating, the specific gravity is ascertained either directly or by a simple calculation. Scales in common use are those of Baumé, as applicable to liquids either more or less dense than water; in the former case the zero is near the top. and in the latter near the bottom of the stem; the graduation is conventional, and the specific gravity is obtained from the reading by means of a series of tables. Another form is that of Tweddell. Hydrometers constructed to measure the purity, density, or degree of concentration of particular liquids receive special names, as alcoholometer, lactometer, etc.
    • n hydrometer An instrument used for measuring the velocity or discharge of water, as in rivers, from reservoirs, etc.
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Chambers's Twentieth Century Dictionary
    • n Hydrometer hī-drom′et-ėr an instrument for measuring the density or specific gravity of solids and liquids by flotation, consisting of a weighted glass bulb or hollow metal cylinder with a long stem: a current-gauge
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Webster's Revised Unabridged Dictionary
Hydro-, 1 + -meter,: cf. F. hydromètre,
Chambers's Twentieth Century Dictionary
Gr. hydōr, water, metron, a measure.


In literature:

Bless my hydrometer, I should say so!
"Tom Swift and his Undersea Search" by Victor Appleton
The greater the amount of solid matter dissolved in the sirup, the higher will be hydrometer float.
"Woman's Institute Library of Cookery, Vol. 5" by Woman's Institute of Domestic Arts and Sciences
The hydrometer, which measures air humidity, was also invented.
"Our Legal Heritage, 5th Ed." by S. A. Reilly
It was Marion Rose, up by the hydrometer that looked something like a lone beehive perched on a wild slope by itself.
"The Lookout Man" by B. M. Bower
This gave her a solution of pearl ash or potassium carbonate whose concentration she tested with an egg as a hydrometer.
"Creative Chemistry" by Edwin E. Slosson
An instrument much used on the Continent is the Beaume hydrometer.
"The Chemistry of Hat Manufacturing" by Watson Smith
Nearly any filling station has the necessary hydrometer.
"If You're Going to Live in the Country" by Thomas H. Ormsbee and Richmond Huntley
Next take 5 pints water, add hydrosulphite slowly, stirring gently until a reading of 1100 is shown (SG 1.1) on the hydrometer.
"Vegetable Dyes" by Ethel M. Mairet
He improved the hydrometer.
"Fragments of science, V. 1-2" by John Tyndall
Since its strength is apt to vary, however, it is best to mix the electrolyte with the aid of the hydrometer furnished with the battery.
"Electricity for the farm" by Frederick Irving Anderson
The combination is called a hydrometer-syringe, or simply hydrometer.
"The Automobile Storage Battery" by O. A. Witte
There's even a hydrometer for testing the batteries.
"The Blue Ghost Mystery" by Harold Leland Goodwin
Hydrometer improved by Alhazen, ii.
"History of the Intellectual Development of Europe, Volume II (of 2)" by John William Draper
Hydrometers are graduated differently for liquids of different weights.
"Soap-Making Manual" by E. G. Thomssen
It marks then 34 at the hydrometer.
"Hand-Book of Practical Cookery for Ladies and Professional Cooks" by Pierre Blot
Beaume Hydrometer, $1.25 (with glass).
"Photogravure" by Henry R. Blaney
It should be wider than the hydrometer, and always filled to the brim.
"A Treatise on Meteorological Instruments" by Henry Negretti
Thermometers and Hydrometers for scientific and other purposes.
"Scientific American, Vol. XXXVII.--No. 2. [New Series.], July 14, 1877" by Various
A hydrometer that is especially adapted to milk is called a lactometer.
"The Book of Cheese" by Charles Thom and Walter Warner Fisk
The hydrometer of A. Baume, which has been extensively used in France, consists of a common hydrometer graduated in the following manner.
"Encyclopaedia Britannica, 11th Edition, Volume 14, Slice 2" by Various

In news:

Richard Sanders uses a hydrometer to check the specific gravity of syrup in the evaporator at Maple Creek Farm.