the Strengths and Vahies of Spirituous Liquors. 209. 



each other as is alrcadv^ described in the last section, the spe- 

 cific gravity of a hquor weighing seven pounds thirteen 

 ounces avoirdupois, or 5-l687"5 grams per wine-gallon, will 

 be 937-59. Now sir Charles Blagden tells us, that, although 

 no temperature is mentioned iu the statute, yet the under- 

 standing of the trade is, that it means that the diluted spirit 

 thus spoken of should be considered as being at 55°; whilst 

 others contend that the temperature should be rated higher, 

 for the following reason. It seems tliat, at the time of mak- 

 ing the fundamental experiment on which the statute was 

 founded, the spirit which is there described was produced by 

 lowerino; either alcohol, or some other kind of rectified spirit, 

 to the strength there spoken of with water, and immediately 

 weighing it; under which circumstances it was then found 

 to weigh 7 pounds 13 ounces per gallon, and to be one to 

 six under proof. Now, if this was really the case, the mix- 

 ture could not probably be lower than 60°. We will how- 

 ever suppose that the truth lies somewhere between them, 

 and that the temperaturewas in fact 574". Now we find, 

 from Mr. Gilpin's tables, that a spirit which is of the spe- 

 cific gravity of 937-59 at 57^° is similar to one composed 

 of 100 parts of water by weight, and S6| of his alcohol of 

 the specific gravity of S'25. at 60°, and of which it contains 

 a -quantity which would be by measure, when at 60", equal 

 to -5278 of the bulk of the compound at 57i°. But proof 

 spirit is, by the directions of the act, ?.ccording to the con- 

 struction of it w hich we adopt, to jontain 7-Cth3 of this 

 proportion, or -6157 of its quantity of such alcohol by mea- 

 sure when at 60''; that is, it will be equal to a compound 

 which will be found by the same tables to have exactly the 

 specific gravity of 92O at 60'^. This appreciation, therefore, 

 of proof spirit has been adopted by the authors of this tract 

 in all the instruments which they have made for many years, 

 and appears now to have become that of the trade in gene- 

 ral, 'i'iie wine gallon at 60° of spirit of this strength weighs 

 7 pounds 10 ounces and 10-47 drachms avoirdupois; and 

 the same measure at 55", 7 pounds 10 ovinces and 15-59 

 drachms. 



The commissioners of the customs have, however, (ac- 

 cording to the statement of Mr. Ramsden, in his *' Account 

 of Hxpcriments to determine the Specific Gravities of Flu- 

 ids, thereby to obtain the Strength of Spirituous Liquors," 

 jtrintcd iu 1792,) been in the habit of considering proof 

 sjjirit as weighing 7 pounds 12 ounces jicr gallon, at 55°, 

 which would, according to the foregoing estimation of the 

 relation between this weight and measure, give no less than 



Vol. XVI. No. C3. O 9^28 



