FAEMYAED MANUEE 



325 



manure are apt to prove misleading. Any statement 

 of limits or averages must therefore be accepted with 

 considerable reserve. For example, it may be said that 

 average samples of mixed manure contain from 0'5 to 

 0*75 per cent, of nitrogen, from 0'2 to 0'3 per cent, of 

 phosphoric acid and from 0'3 to 0'4 per cent, of potash. 

 These, however, are not the limits of variation. Some 

 samples are richer and others are of much poorer quality 

 and such are by no means uncommon. 



For any ingredient O'l per cent, is equal to very 

 nearly 2J Ibs. per ton. According to Warington, l 

 average samples contain from 9 to 15 Ibs. of nitrogen, a 

 similar quantity of potash and from 4 to 9 Ibs. of phos- 

 phoric acid per ton. Calculating from th>e mean of the 

 figures given above, each ton of manure should contain 

 about 14 Ibs. of nitrogen, 8 Ibs. of potash and 5| Ibs. of 

 phosphoric acid. 



The following analyses may be taken as typical, and 

 serve to illustrate some of the points referred to : 



ANALYSIS OF MIXED MANURE, FRESH AND ROTTED (VOELCKER). 



Chemistry of the Farm." 



