58. Gendar's Hydrometer

58. Gendar's Hydrometer. 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 percent, above and below proof.

This is inserted for the convenient comparison of the American standards. Tables of other areometers reduced to specific gravity will be found in Nob. 6155, etc..

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, 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 a liquor which corresponds to 50 degrees of Tralles' hydrometer at the temperature of GO degrees Fah." Proof spirit is, therefore, by law, of the alcoholic strength of 50 per cent, by volume, having a specific gravity of 0.9335, or a mixture of equal quantities of absolute alcohol at the specific gravity of 0.793, and distilled water at 60° Fah. In other words, proof spirit is one-half pure water and half absolute alcohol.

To ascertain what strength any liquor above proof by the Gendar hydrometer would be by the Tralles hydrometer, add 100 to the given proof if above proof, or deduct, if below proof, from 100 on the Gendar scale, and divide

by 2. Say a liquor is at 40 above P. on the Gendar scale.you then add 100, making 140, and divide by2, which will show 70 on the Tralles'scale. If below P. deduct the proof from 100 and divide the remainder by 2. Say a liquor is 35 below P., consequently you have a remainder of 65, and divide the 65 by 2, which will show 321/2 onTralles' scale. Having ascertained the degree of strength of any liquor by volume on Tralles' scale above 50 (which is proof), multiply the degrees by 2, and cut off the two right hand figures, and it will show the degrees above proof on Gen-dar's scale. Thus we will suppose the spirit to show 70 per cent, strength on Tralles' scale. We thereforo multiply 70 by 2, which gives us 140; we now cut off the two right hand figures, thus, 1.40, and find that the liquor is 40 above proof on Gen-dar's scale.

Or suppose a liquor is below 50 on Tralles' scale (which is below proof). To find what degree it is below on Gendar's scale, multiply the degrees on Tralles' scale by 2 and add a number sufficient to make 100; the number required to be added will show the degree below proof.