208 



THE SYSTEM OF FAEM-YARD MANURING. 



if these are filled up in proportion as the plant grows, so 

 that at last the earth in the trench is on the same level 

 with the arable surface, it is always found that the tubers 

 are formed only in the topmost layer, none at a greater 

 depth, and not more in number than if the seed-potatoes 

 had been planted only IJ or 2 inches deep in the arable 

 surface soil : and on gathering the crop it is observed 

 that the roots below the arable surface have died away. 



With clover, the case is reversed ; and although the 

 arable surface soil at Kotitz, for example, is decidedly 

 richer in substances nutritive for clover than that in 

 Cunnersdorf (yielding a potato crop higher by one- 

 eighth), this had no effect upon the clover, which receives 

 its principal nutriment from the deepest layers of the soil. 



We now proceed to an analysis of the returns which 

 were obtained, in the Saxon experiments, by employing 

 farm-yard manure upon the plots of the same fields, the 

 crops of which in their unmanured state we have just 

 been considerino;. 



Produce, per Saxon acre, of the fields dressed ivitli farm-yard manure. 



* The clover crop failed from excessive wet. 



