PKEPAKATION OF THE ALCOHOLIC LIQUID. Ill 



it suffices to determine its specific gravity by testing with an areo- 

 meter and to find the indicated figure in Table I. (Hehner's 

 alcohol table). The figure in the next horizontal column gives 

 the per cent, by weight and the next the per cent, by volume of 

 alcohol contained in the spirits of wine examined. Tables II., 

 III., and IV. give data relating to the proportion between the 

 specific gravity, and per cent, by weight and volume of spirits of 

 wine of various concentration as well as the decrease in volume 

 by mixing with water. Table V. shows the relation between the 

 statements of Tralles's alcoholometer and a few others used in 

 different places. 



The specific gravity as well as the volume of spirits of wine 

 varies with the temperature, and the statements of the areometer 

 for temperatures above the normal of 59 F. require a corre- 

 sponding correction, the execution of which is simplified by the 

 use of Tables VI. and VII. It being desirable, especially 

 during the cold season of the year, to raise the temperature of 

 the spirits of wine by mixing with water, Table VIII. shows 

 how much water has to be added in order to obtain from 100 

 liters (105.6 quarts) of spirits of wine of known strength 

 whiskey of any desired concentration. 



In order to know exactly the yield of acetic acid which is ob- 

 tained from a given quantity of alcohol, the acetic acid con- 

 tained in the vinegar added must necessarily be taken into ac- 

 count as well as the alcohol in the beer, which is of course 

 converted into acetic acid. Ifc is best to make the content of 

 alcohol in the alcoholic liquid so that it produces vinegar whose 

 strength corresponds with that of the vinegar added. If, for in- 

 stance, vinegar with 7 per cent, of acetic acid is used, alcohol of 

 7.6 to 7.7 per cent, by weight would have to be employed accord- 

 ing to the table on p. 108. The following compilation shows the 

 manner of preparing alcoholic liquid according to rational prin- 

 ciples. 



Suppose vinegar with 7 per cent, acetic acid is to be prepared. 

 There would be required 



Spirits of wine of 7.6 to 7.7 per cent, by weight 100 liters (105.6 quarts). 

 Vinegar with 7 per cent, of acetic acid . . 10 " ( 10.56 " ) 

 Beer 30 " ( 10.56 " ) 



