INCREASE OF CROPS BY USE OF FERTILIZERS 17 



results than any of the pure chemical substances. The 

 superiority of superphosphate is very often due to the fact 

 that, being soluble, it distributes itself in the soil much 

 better than less soluble compounds. Where there is perma- 

 nent herbage, rapidity of action is of less account, and distri- 

 bution is somewhat slow, since manure applied to a pasture 

 must penetrate the matted surface before it can reach the 

 true soil. Any phosphatic manure applied to a soil is, in any 

 case, rapidly fixed in a relatively insoluble form, but the 

 more finely divided the fertilizer is, the better will be 

 the distribution. The effect of phosphates, in raising the 

 quality and feeding value in hay crops, is a very important 

 point. The most nutritious pastures in England and the 

 best dairy pastures in France are those that are richest in 

 phosphates, and it has also been shown that the best wines 

 contain the greatest quantity of phosphoric acid, and that 

 there is a close connection between the amount of phosphates 

 in the soil, the amount of phosphates in the wines, and the 

 quality of the wines. 



As has been indicated above, many of the ultimate effects 

 of phosphatic manures must be attributed to secondary 

 results. Basic slag applied to the soil on Tree Field at Cockle 

 Park not merely gave an increased quantity of mutton and 

 hay, but also almost doubled the proportion of phosphoric 

 acid in the hay, so that the amount of phosphoric acid 

 consumed per acre by the animals was quadrupled by the 

 addition of phosphatic manures. The percentage of nitrogen 

 in the soil is also increased very markedly. As the result 

 of eleven years' treatment on Tree Field, the amount of 

 nitrogen in the soil has been increased from 0-185 to 0*236, 

 where slag and superphosphate have been used. That is to 

 say, the nitrogen has been increased to the extent of about 

 850 pounds of nitrogen per acre. When nitrogenous manures, 

 sulphate of ammonia in some years and nitrate of soda in 

 others, were used on other plots, very little increase in nitro- 

 gen took place. Some of the results obtained by using basic 

 slag are really due to the fact that the soil has become very 

 much richer in nitrogen, but, of course, the whole credit of 

 v. 2 



