MINERAL MATTERS LOST IN CROPS. 'J33 



The arable soil of the Cunnersdorf field received, 

 accordingly, in the farm-yard manure, more phosphoric 

 acid and more potash than had been carried off by the 

 corn-crops. 



In this calculation, it is a question of no importance 

 how much of the rye or oats was carried off". More 

 than the field produced could not be carried away, and 

 if less were removed the only effect would be that 

 phosphoric acid and potash would accumulate all the 

 more in the field. 



Mctusegast. 



Phosphoric acid Potash 

 lbs. lbs. 



The arable soil lost by the rye-grain, barley -grain, 



yL potatoes, yV clover ..... 35"4 18"1 



The arable soil received in -^ of the clover crop 22-0 62*0 



Loss 13-4 Gain 43-9 



Kotitz. 



The arable soil lost in the rye, oats, and in 



the -^Q of the potatoes and clover 

 It received in the clover .... 

 Loss .... 



The calculation is about tlie same for the field at 



* The quantity of potash is calculated here upon the proportion of 

 phosphoric acid in corn, one part by weight of potash to two parts by 

 weight of phosphoric acid. 



