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HYDROMETER. An instrument for measuring the density of fluids; being immersed in fluids, as in water, brine, beer, brandy, &c., it determines the proportion of their densities, or their specific gravities, and thence their qualities.
     2. By, the Act of Congress of January 12, 1825, 3 Story's' Laws U. S. 1976, the secretary of the treasury is authorized, under the direction of the president of the United States, to adopt and substitute such hydrometer as he may deem best calculated to promote the public interest, in lieu of that now prescribed by law, for the purpose of ascertaining the proof of liquors; and that after such adoption and substitution, the duties imposed by law upon distilled spirits shall be levied, collected and paid, according to the proof ascertained by any hydrometer so substituted and adopted.

A Law Dictionary, Adapted to the Constitution and Laws of the United States. By John Bouvier. Published 1856.
References in periodicals archive ?
Keep adding liquid sugar and measuring with the hydrometer until you achieve the desired 24 brix level or come close to it (better a little under than a little over).
Once both solutions had reached a temperature of exactly 72.4 degrees Fahrenheit, they were tested with a hydrometer. The stirred drink had dropped down from 80 proof to 60, meaning it had a final 30 percent ABV.
Hydrometer selected Aras for its powerful integrations with leading applications such as SAP, and for its flexible, open architecture which gives the company the option of tailoring and implementing the solution independently, with Aras or with their partner of their choice.
* place the hydrometer gently into the sample at least 0.5 in.
After the initial issuance of these new meters by the type commanders, each submarine will be required to have two of the new DMA35N's onboard as well as two old style hydrometers of each range for back-up purposes (one of these being a reference).
This is a definite improvement over the older hydrometer method, which required at least a full cup or two of coffee to work.
Processors who need to keep track of sucrose solids have a wide array of options, from hand-held hydrometers to on-line refractometers and spectroscopes.
Some country wine makers dismiss the hydrometer, Campden tablets, fermentation lock, and even wine yeast as extraneous paraphernalia.
Twaddell: The Twaddell hydrometer, developed in England between 1812 and 1839, consisted of a series of spindles with graduations from 0 to 174.
One item I wouldn't do without is a hydrometer. The fancy name shouldn't scare you off!
The process control Digital Electronic Hydrometer utilizes Hall sensor technology that allows for continuous real-time monitoring, logging and controlling of liquid density/ specific gravity during a mixing, blending or plating operation.
The test is performed with a hydrometer, which is a sealed glass tube that contains a calibrated scale in degrees Baume.