222 
Analyses of the Mineral Ingredients of the Hop. 
Several salts of potash are well known in commerce, and like- 
wise to the agriculturist. Nitrate of potash or saltpetre is one, 
and common pearlash is another. 
Saltpetre contains about 47 per cent, of potash, and pearlash 
about 68 per cent. By calculation, therefore, we find that 64 lbs. 
of potash taken from the land by a crop of hops would be re- 
placed by 136 lbs. of saltpetre, at a cost of about 32*., or by 
94 lbs. of pearlash, at a cost of about 33s. 
The weights of saltpetre or pearlash given above would supply 
the deficiency of potash, supposing the whole crop, including 
bine, leaves, and hops, were removed from the land. But if the 
bine and leaves be allowed to rot on the ground, about one-sixth 
less than the preceding amounts would be sufficient. The im- 
propriety therefore of removing the bine, &c. from the land, as 
is too often the case, is very apparent. 
One of the most important points to be deduced from these 
analyses is the preparation at a reasonable expense, of a manure 
which shall contain all the necessary mineral ingredients for the 
growth of the hop. Being engaged in the analyses of various 
other samples of the hop, I am now unwilling to offer as perfect 
any manure for the hop until the comparison of different varieties 
shall have shown that the hops in divers localities agree in the per 
centage of their various constituents. 
It will be seen by reference to the analyses, that besides potash, 
the hops contain phosphoric acid, lime, magnesia, common salt, 
and silica. About 3 cwt. of guano would supply the necessary 
amount of phosphates. The chloride of sodium would be amply 
supplied by 1 cwt. of common salt. Lime and magnesia are 
doubtless found in sufficient quantities in the land, or if not they 
can easily be supplied. The silica, perhaps, may be found in 
sufficient quantities in the land, though it might be better to sup- 
ply both silica and potash together, in the shape of silicate of 
potash. This compound, however, is not at present an article 
of commerce, but there is a probability that it will soon be manu- 
factured on a large scale. The sulphuric acid can be supplied 
by gypsum. 
Either of the following mixtures might be worth trial for pro- 
moting the growth of the hop : — 
No. 1. — Manure for an Acre of Hops. 
s. d. £,. s. d. 
3 cwt. guano, at . .80 per cwt. . .140 
1 cwt. common salt, at .10 , , . .010 
1^ cwt. saltpetre, or 1 \ cwt. 
•ilicate of potasii at . 26 6 ,, . . 1 19 9 
1 J cwt. gypsum . .10 , , . .009 
Cost per acre . . . . .356 
