348 



BOARD OF AGRICULTURE. 



A careful comparison of these few figures shows not only 

 the striking difference in the' percentage of sugar in the 

 juice of several well-known varieties, but it makes conspicu- 

 ous the fact that the different kinds lose their moisture at 

 quite different rates under ordinary circumstances. The 

 increase in the sweetness of the grape is not due to a pro- 

 cess of after-ripening, but to a loss of moisture, in conse- 

 quence of keeping, after their removal from the vine. 



II. 



Main Organic Acids. 



An examination of the juice from the ripe grape proved 

 the absence of malic acid and oxalic acid, and established 

 the presence of varying quantities of tartaric acid in a free 

 state. 



III. 



Ash Constituents of the Fresh Juice of the Ripe Grape. 



The nnfermented and fermented juice obtained Oct. 9, 

 1874, contained its essential mineral constituents in the 

 following proportion : — 



UNFERMENTED JUICE. 



Potassium oxide . 

 Sodium oxide 

 Calcium oxide . 



Per cent. 



, 50.85 



.48 

 . 3.69 



FERMENTED JUICE. 



Potassium oxide 

 Sodium oxide 

 Calcium oxide 



Per cent. 



, 40.09 

 , 6.85 



