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The Hydometer
desired to know the per cent by weight, it may be ascer tained from the per centage in volume of the liquid at 60° Fah. by Table III., on preceding page.
We have already stated that Tralles' Hydrometer is the instrument used by the United States Government to ascertain the strength of imported spirits; but, by the Tax Law recently passed by Congress, the amount of revenue which will flow into the National Treasury annually from the trade in domestic liquors, renders it a matter of some importance to ascertain the real strength or per centage of alcohol, with expedition and accuracy; besides, the manufacturers and liquor merchants have always been accustomed to buy and sell their spirits at a proof standard, and it has, therefore, been deemed necessary, if possible, to adopt some instrument with a proof scale in harmony with the scale of Tralles' hydrometer. It has, also, been urged against the hydrometer of Mr. Tralles, that being made of glass it is too liable to be broken when carried around by the inspectors of Internal Revenue.
The Standard Hydrometer and Thermometer, made by Messrs. W. T. and T. V. Gendar, of this city, seems to answer all the above requirements. It is graduated in conformity with Tralles' instrument in 200 parts above and below proof. Therefore, one part or degree of Tralle's scale is just equivalent to two parts of Gendar's scale. This hydrometer has a thermometer that accompanies it, which is graduated so as to show at a glance the true per centage of spirits at any temperature, the use of tables may, therefore, be dispensed with. Gendar's hydrometer is made of silver; another advantage it has over the glass instrument.
This hydrometer is certified to be in accordance with the laws of the State of New York. It was adopted by the State of Pennsylvania, June 15th, 1861, and has been used since April 5th, 1851, by all the distillers, inspectors, and dealers in liquor in this city, as the only instrument by which they would buy and sell. It was again adopted, October, 1862, and is now used by the inspectors appointed by the collectors of Internal Revenue under the new National Tax Law of 1862. This instrument may, therefore, be said to be in general use throughout the whole country.
Annexed we give a comparative view of the scales of Tralles and Gendar, the former used by the revenue officers of the United States for imported liquors, and indicating the per cent by volume of alcohol in spirituous liquors, and the latter used throughout the whole country for domestic liquors, determining the per cent above and below proof.
The first column of the table exhibits the specific gravities at 60° Fah., for mixtures of pure alcohol and water;-taking water at the temperature of its greatest density, at 4° centigrade scale, or about 39.5° Fah., as 1.0000, and, therefore, having at 60° Fah., a specific gravity of 0.9991. Of the above mixtures, each 100 gallons or measures contain the number of gallons or measures of alcohol indicated in the second column (Tralles' Hydrometer scale), if measured at 60° Fah.
In the Tralles' hydrometer scale there is no reference to proof of any denomination; and in that of Gendar's there is but one proof, marked P. on the Hydrometer; the others, such as 2d, 3d and 4th proofs, were, at all times, incorrect and deceptive. The National Tax Law, of August 1st, 1862, says, that, "the term proof shall be construed, and is hereby declared to mean, that proof of 0.7939 100 8157 95 8332 90 8488 85 8631 80 8765 75 8992 70 9013 65 9126 60 9234 55 9335 50 9427 45 9510 40 9583 35 9646 30 9700 25 9751 20 9802 15 9857 10- Hyd'ter.
Gendar's 100 Gendar's