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cessary, for there is no fibrous matter rendered 
soluble in the process, and a part of the manure is 
lost. 
The best farmers in the west of England use it 
as fresh as it can be procured ; and the practical 
results of this mode of applying it are exactly con- 
formable to the theory of its operation. The 
carbonic acid formed by its incipient fermentation 
must be partly dissolved by the water set free in 
the same process ; and thus become capable of 
absorption by the roots of plants. 
The effects of the sea weed as manure must 
principally depend upon this carbonic acid, and 
upon the soluble mucilage the weed contains ; and 
I found that some fucus which had fermented so 
as to have lost about half its weight, afforded less 
than -jV of mucilaginous matter ; from which it 
may be fairly concluded that some of this substance 
is destroyed in fermentation. 
Dry straw of wheat, oats, barley, beans and 
peas, and spoiled hay, or any other similar kind of 
dry vegetable matter is, in all cases, useful manure. 
In general, such substances are made to ferment 
before they are employed, though it may be doubted 
whether the practice should be indiscriminately 
adopted. 
From 400 grains of dry barley straw I obtained 
eight grains of matter soluble in water, which had 
a brown colour, and tasted like mucilage. From 
400 grains of wheaten straw I obtained five grains 
of a similar substance. 
There can be no doubt that the straw of different 
crops immediately ploughed into the ground affords 
