On, Liquid Manure. 13 



The smell of this liquid, especially in summer, is very bad ; 

 the decomposition of the animal matters proceeds more rapidly 

 in hot weather, and in a dry season like the last the smell of 

 sulphuretted hydrogen is so strong that, except on a rainy day, 

 the liquid cannot be pumped over the manure-heap without 

 creating a nuisance. 



The soil on all the fields of the College farm contains a good 

 deal of clay ; and, though many fields are called light, the soil is 

 only light in virtue of the limestone and gravel that abound in 

 those places. Separated from the stones, the soil from these so- 

 called light fields is quite stiff and heavy, since it contains hardly 

 any sand, and is composed chiefly of clay and lime. 



We have applied our tank-liquid by itself on various occasions, 

 but have never seen much good produced by it. The soils on the 

 College farm and neighbourhood derive, I believe, little or no 

 benefit from liquid manure. In a subsequent page I shall state 

 the reasons why land like this is not benefited by it. On account 

 of the inefficacy of this liquid when applied by itself on our 

 farm, and the expense of distributing it, the liquid manure is 

 now rarely used by itself, but is pumped when required over 

 the manure-heap. 



Abundance of straw being produced on the farm, which in 

 some way or other has to be converted into manure, the dung in 

 the pit is generally drier than it is desirable it should be, and 

 affords an excellent opportunity for the absorption of the tank- 

 liquid. 



Seven thousand grains of tank-liquid collected in 1857 gave 

 on evaporation to dryness 12*110 grains of solid matter, which 

 furnished on burning 7*394 grains of mineral matters. 



The mineral matters were found to contain in 100 parts : 



100*00 



Seven thousand grains evaporated to dryness with the addition 

 of hydrochloric acid gave a residue that produced on burning 

 with soda-lime 2*296 grains of ammonia. 



The residue from another 7000 grains evaporated without acid 

 only yielded *303 of nitrogen. 



