E. J. Russell and E. H. Richards 



529 



In all cases, except one, there is an increase in the amount of 

 ammonia : the exception is a sample of manure that had been stored 

 some time before the experiment began, and had lost most of its 

 ammonia. 



As the temperature rose this action became more pronounced, 

 and at 26° C. the loss of complex nitrogen compounds and the gain of 

 ammonia was considerably greater than at about 15°. 



Z9 



•7 



A<^ 



/ 



9 



y^rJ/yi/fr 



So D/iY3, 



Sj days 



Fig. 7. Changes in nitrogen compounds in farmyard manure (bullock manure) 

 stored in the laboratory under anaerobic conditions at different temperatures. 



In two out of four cases the gain in ammonia nearly balances the 

 loss of complex nitrogen compounds : this happened when the manure 

 was most closely packed. With looser packing, where some air would 

 be left in the early stages, the ammonia produced was not equivalent 

 to the complex nitrogen compounds broken down, and there was a 

 deficit on the total nitrogen amounting to 4-5 %. With tighter packing 

 and strictly anaerobic conditions there was no appreciable loss. 



