AMOUNT OF ALCOHOL IN WINE. 155 



was superfluous, its specific gravity was taken ; it gave 

 exactly 10*5 per cent, alcohol. This spirit in the 

 same platinum vessel gave the first sign of boiling 

 at 197-6F. 92 C. and boiled completely at 199*4 F. 

 93C. 



These are the same temperatures at which wine 

 containing 10'5 alcohol, and 1*64 per cent, extract 

 boiled. So far one might imagine the ebullioscope 

 could be trusted. But then we overlook the uncer- 

 tainty of a whole degree in the temperature in the 

 first place, and secondly, the effect of the solid mat- 

 ters of the wine, which amounts here to half a 

 degree, and might, in wines containing a great deal 

 of sugar, rise to 2y degrees C. = 8 degrees E. 



For these reasons I have been led to consider the 

 ebullioscope as useless in cases where accuracy is 

 required. 



Silbermann has made use of another method of 

 ascertaining the alcoholic contents of wine. He 

 starts from the point that heat renders alcohol much 

 more elastic than water, and makes use of an instru- 

 ment for determining the quantity of alcohol, the 

 construction of which we will describe as simply as 

 possible. A thermometer tube with a bulb is filled 

 with water, and dipped into a liquid warmed to 

 77 F. 25 C. ; the point at which the water in the 

 tube stands is marked, the liquid warmed to 122 F. 

 50 C., and the point to which the water then rises 

 likewise marked. Then let the apparatus be filled 



