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GRAPE CULTURE AND WINE-MAKING. 



In determining specific gravities, water is assumed as the unit, 

 its weight being denoted by 1, or, for convenience of notation, by 

 1000. If the areometer indicates the specific gravity of a fluid 

 to be more than 1000, it is by so much heavier than water ; if 

 less than 1000, it is by so much lighter. Thus, if a solution of 

 sugar in water has a specific gravity of 1010, we understand that 

 if a certain number of cubic inches of water weighs 1000 ounces, 

 the same quantity, by measure, of the fluid weighs 1010 ounces : 

 such a solution contains 1000 parts of water and 10 parts of sugar. 



In comparing the degrees indicated by Beaume's areometer in 

 fluids containing sugar with their specific weight, the following 

 table will be found useful : 



By the aid of this table it will be easy to calculate how much 

 sugar is contained in any solution. For instance, if a solution 

 shows 15° B. (=1114 specific gravity by the table), we have to 

 ascertain how many cubic centimetres of sugar are contained in 

 a given quantity, say 1000 centimetres. Now sugar has a specific 

 gravity of 1600 ; that is, one cubic centimetre weighs 1600 grains, 

 while one cubic centimetre of water weighs 1000 grains. We 

 will indicate the unknown quantity, the amount of sugar, by x. 

 Then, 



_ (1114-1000)xl000 _ 114,000 _ 

 '^~ 1600-1000 ~ 600 ~ 

 That is, 190 cubic centimetres of sugar were contained in 1000 

 cubic centimetres of the fluid. Consequently, there were in the 

 1000 centimetres of fluid, 



Sugar 190 cubic centimetres. 



Water ^810 " 



1000 " " 



The above are the quantities by measure ; by weight they are, 



Water 810 cubic ccntimctrcs=810 grains. 



Sugar (11U-810)=314 " " _314 " 



1114 " 



For practical use, it is, however, more convenient to have the 

 stem of the areometer graduated in such a manner as to indicate 

 the quantity of a body dissolved in a certain quantity of the fluid. 



