198 



THE SYSTEM OF FARM- YARD MANURING. 



produce the same relative proportion of corn and straw 

 as, for example, the land at Oberbobritzsch. 



It is a very essential part of the farmer's business to 

 study the nature of his field, and to discover which of 

 the nutritive substances, useful to plants, his land con- 

 tains in preponderating quantity : for thus he will know 

 how to make a right selection of such plants as require 

 for their developement a superabundance of these con- 

 stituents ; and he will obtain the greatest profit from his 

 field, when he knows what nutritive substances he 

 must supply in due proportion to those which are 

 already in abundance. 



Two fields, in which the total amount of nutriment 

 is unequal, but the relative distribution of the sub- 

 stances is the same, will produce crops differing in 

 quantity, but agreeing in the relative proportion be- 

 tween corn and straw. 



Such a relation, for example, exists between the 

 field at Oberbobritzsch and the field at Mausegast. If 

 the crop of corn and straw in the former is expressed by 

 ~K. + aK St, the crop in the latter = l^K + l^K St. 



The fields are evidently cultivated in both places 

 with great care and skill, and the soil is so uniformly 

 mixed, that when we know the corn and straw crop of 

 the one, and the straw crop of the other, we can calcu- 

 late the corn crop of the latter from the above formula. 



Potatoes, 1852. In the subjoined table, the vertical 

 lines show the potato crops from five different fields in 

 the year 1852. 



1852. POTATOES. 

 Cunnersdorf, Mausegast, Kotitz, Oberbobritzsch, Oberschona. 



