THE GRAPE. / 



In those cases, therefore, where the fruit is allowed, 

 after pressure, to ferment with skins, stones, and 

 juice; or where the grape stones in larger or smaller 

 quantities are included in the fermentation, a certain 

 quantity of tannic acid may be obtained from them, 

 although the amount, owing to the hardness of the 

 covering of the seeds, will be but small. The same 

 holds good with respect to the stalks of the grapes, 

 which contain a good deal of tannic acid, and are 

 often allowed to ferment. 



Looking at wine, then, from a chemical point of 

 view, the vine, with all its constituents, deserves our 

 consideration in the first place. 



The organic components of the wood are the com- 

 mon ones. Science is not, and perhaps never will be, 

 in a position to bring the structure of plants into 

 connexion with the nature of their products. But 

 what it can do, and in modern times has earnestly en- 

 deavoured to achieve, is to investigate the organic 

 constituents, and the relation between the necessary 

 ingredients of the soil, and the nature of its vegetable 

 products. 



All wines contain cream of tartar, a salt which 

 consists of tartaric acid and potash. The quantity 

 and quality of the grape juice is connected, therefore, 

 with the existence or non-existence of potash in the 

 ground. Potash preponderates in the ^vliole plant, 

 and in all its parts, in the leaves and fruits, and also 

 in the stem and boughs. If, therefore, a sufficient 



