The Art of Perfumery, and Methods of Obtaining the Odors of Plants / With Instructions for the Manufacture of Perfumes for the Handkerchief, Scented Powders, Odorous Vinegars, Dentifrices, Pomatums, Cosmetics, Perfumed Soap, Etc., to which is Added an Appendix on Preparing Artificial Fruit-Essences, Etc.

by G. W. Septimus Piesse

Here,

54 + 100 = 154 and 4062.183 = 26.3778 galls., or 26 galls. 3 pts.
————
154

which, divided by 4, gives 6 gallons, 4 pints, 15 oz.

Suppose the spirit to be 60 overproof,—

4062.183 {one-fourth of which is equal
then ————— = 25.388 gallons, {to 6 gallons, 2 pints,
(100 + 60) {15-1/2 oz.

This rule is founded on the following data. As a gallon of water weighs 10 lbs., it is obvious that the specific gravity of any liquid multiplied by 10 will give the weight of one gallon. The specific gravity of absolute alcohol is 0.793811; hence, the weight of one gallon will be 7.93811 lbs., and its strength is estimated at 75.25 overproof.

4 equivalents of alcohol = 46 × 4 = 184,
and
23.17936 gallons × 7.93811 lbs. per gallon, also = 184.0003094.

Hence it appears that 23.17936 gallons of absolute alcohol are equal to 4 equivalents. By adding the overproof per centage (75.25) to 100, and multiplying by the quantity (23.17936 gallons) we get the constant number 4062.183.

The rule might have been calculated so as to show at once the equivalent, without dividing by 4; but it would have required several more places of decimals; it will give the required quantity to a fraction of a fluid drachm.

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