24 



elements of which the plant is composed, as well as the sources from 

 which they are derived : 



Carbon ... ... \ Amounting to about 90 per cent., and 



Hydrogen ... ... / derived by the vine from the air and 



Oxygen ... ... / rain. 



Sodium 



Amounting to about 4 per cent. 



These elements are always far 

 Chlorine ... ... ) , i ,1 . -, -, ^ 



more abundantly provided in the 



soil than is necessary to the plant. 

 Silicon 



Nitrogen ... ... -. Amounting to something over 4 per 



Phosphorus ... ... cent. Derived like the last from 



Potassium ... ... [ the soil in which they are only 



Calcium (lime) ... J present to a limited extent. 



Of these fourteen elements, combined together in varying numbers 

 and proportion, the almost infinite number of substances found in the 

 vine and wine are made up. We see from the above table that the 

 last four, viz. : Potassium, phosphorus, nitrogen, and calcium (or 

 lime) are the only ones we need consider, as all others are either 

 derived from the air and rain or are so abundantly present in all soils 

 as to be practically inexhaustible. The presence of more or less of 

 these four important elements renders a soil valuable or worthless, 

 and the predomination of any one of them will render such a soil 

 especially suitable for one class of plants. A soil rich in nitrogen is 

 most suitable for wheat, colza, tobacco, &c. ; one rich in phosphorus is 

 better suited for turnips, maize, sugar cane, &c.; whilst for vines 

 potash is the most important element, at least as far as the 

 production of fruit is concerned the presence of phosphorus and 

 nitrogen has more influence on the production of wood. Now, although 

 vines are cultivated with the object of obtaining fruit, there must 

 be wood for the fruit to grow upon. We must have sufficient of all 

 the necessary elements, but as potash is the one of which the greatest 

 portion is taken away by the fruit, it is the one which should be 

 present in considerable proportion in all soils intended for vines. 



In many cases poor soils give wines of superior quality, especially 

 in a cold climate where a heavy crop would give too weak a wine. 



