ON A MODE OF MANURING VINES. 253 



belonging to a great many different families were sub- 

 jected to trial." {Buchner's Reperiorium, ii. Reihe, xix. 

 Bd. S. 38.) 



ON A MODE OF MANURING VINES. 



The observations contained in the following pages should 

 be extensively known, because they furnish a remarkable 

 proof of the principles which have been stated in the pre- 

 ceding part of the work, both as to the manner in which 

 manure acts, and on the origin of the carbon and nitrogen 

 of plants. 



They prove that a vineyard may be retained in fertility 

 without the application of animal matters, when the leaves 

 and branches pruned from the vines are cut into small 

 pieces and used as manure. According to the first of the 

 following statements, both of which merit complete con- 

 fidence, the perfect fruitfulness of a vineyard has been 

 maintained in this manner for eight years, and according 

 to the second statement for ten years. 



Now, during this long period, no carbon was conveyed to 

 the soil, for that contained in the pruned branches was the 

 produce of the plant itself, so that the vines were placed 

 exactly in the same condition as trees in a forest which 

 received no manure. Under ordinary circumstances a 

 manure containing potash must be used, otherwise the 

 fertility of the soil will decrease. This is done in all wine- 

 countries, so that alkalies to a very considerable amount 

 must be extracted from the soil. 



When, however, the method of manuring now to be 

 described is adopted, the quantity of alkalies exported in 

 the wine does not exceed that which the progressive dis- 

 integration of the soil every year renders capable of being 

 absorbed by the plants. On the Rhine 1 litre of wine is 

 calculated as the yearly produce of a square metre of land 

 (108 square feet English). Now if we suppose that the 

 wine is three-fourths saturated with cream of tartar, a pro- 

 portion much above the truth, then we remove from every 

 square metre of land with the wine only 1*8 gramme of 

 potash. 1000 grammes (1 litre) of champagne yield only 

 1*54, and the same quantity of Wachenheimer 1-72 of a 

 residue which after being heated to redness is found to 

 consist of carbonates. 



One vine-stock, on an average, grows on every square 

 22 



