28 



This does not appear probable, in view of the general fact that, 

 for all soils, the manure can scarcely be said to have increased 

 the amounts of magnesia recovered until the soils to which 100 

 tons per acre had been applied are reached. 



Influence of different amounts of stable manure upon the water- 

 soluble magnesia recovered with distilled water. 



The mean differences of magnesia, as shown for the soils re- 

 ceiving the 200 tons of manure, stand in the relations of 100 

 for the Southern soils to 79.31 for the Northern. 



INFLUENCE OF 5, 10 AND 15 TONS OF STABLE MANURE ON THE AMOUNTS OF 

 NITRIC ACID IN SOILS. 



It was found in the comparative study of nitrates in field 

 soils at various times during the season, that not infrequently 

 less rather than more nitrates were recovered from the soils to 

 which most manure had been applied. In the next table there 

 are brought together the observed amounts of nitrates in the 

 surface foot of the different soil types receiving different fer- 

 tilizations. 



