210 THE SYSTEM OF FAKM-YAED MANURING, 



No one looking at these numbers could divine that 

 they were intended to represent the effects produced upon 

 five different fields by an equal quantity of the same 

 manure, and that too the universal manuring agent. 



Neither in the crop of rye-corn and straw, nor in that 

 of potatoes, oats, and clover, is there the shghtest re- 

 semblance or correspondence ; still less is it possible to 

 discover what amount of manure has been instrumental 

 in producing the increased crops. 



The same quantity of farm-yard manure gave, in the 

 years 1851 and 1853, at Mausegast double, at Cunnersdorf 

 three times, the increase of cereal crops, corn and straw 

 together, that was obtained at Oberbobritzsch : the increase 

 of the potato crop at Mausegast was twice as large as in 

 Kotitz ; of clover, four times more in Mausegast than in 

 Cunnersdorf; and in Oberbobritzsch, ten times as much 

 as in Kotitz. 



The enormous quantity of farm-yard manure put upon 

 the field at Oberschona failed to produce anything like 

 the crop obtained from the unmanured field at Mause- 

 gast. 



The composition of farm-yard manure, as we know 

 from numerous analyses, is on the whole so much alike 

 in all places, that we may suppose without great risk of 

 error that in 100 cwt. of farm-yard manure every field 

 receives the same nutritive substances and in the same 

 quantities. 



The constituents of fiirm-yard manure act everywhere 

 in the same way upon the soil or the earthy particles. 

 Now this apparently involves an irreconcilable contra- 

 diction with the fact that the increase obtained by it is 

 nevertheless everywdiere different, and tliat the dung- 

 constituents supplied will, on one field, set in motion and 

 render available to the cereal or potato plants growing on 



