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come immediately the food of the crop, and the 
gradual decomposition affords a supply for suc- 
cessive years. 
Rape cake , which is used with great success as 
a manure, contains a large quantity of mucilage, 
some albuminous matter, and a small quantity of 
oil. This manure should be used recent, and kept 
as dry as possible before it is applied. It forms an 
excellent dressing for turnip crops ; and is most 
economically applied by being thrown into the 
soil at the same time with the seed. Whoever 
wishes to see this practice in its highest degree of 
perfection, should attend Mr. Coke’s annual sheep- 
shearing at Holkham. 
Malt dust consists chiefly of the infant radicle 
separated from the grain. I have never made any 
experiment upon this manure ; but there is great 
reason to suppose it must contain saccharine matter; 
and this will account for its powerful effects. Like 
rape cake it should be used as dry as possible, and 
its fermentation prevented. 
Linseed cake is too valuable as a food for cattle 
to be much employed as a manure ; the analysis of 
linseed was referred to in the Third Lecture. The 
water in which flax and hemp are steeped for the 
purpose of obtaining the pure vegetable fibre, has 
considerable fertilizing powers. It appears to con- 
tain a substance analogous to albumen, and like- 
wise much vegetable extractive matter. It putre- 
fies very readily. A certain degree of ferment- 
ation is absolutely necessary to obtain the flax and 
hemp in a proper state ; the water to which they 
have been exposed should therefore be used as a 
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