204 MANURING COFFEE. 
perty on the same level as that occupied by land 
naturally the most fertile! M. Ville distinctly says 
that by use of his manure crops were raised on the 
worst chalky soils of Champagne and the sand of the 
‘dunes of Holland, equal to the same level as those 
grown in alluvial soils noted for their productiveness. 
By means of plants with taproots M. Ville asserts 
that he is able to ascertain the constitution of the 
subsoil as well as the soil, and in both cases with 
perfect accuracy. We cannot help quoting once 
more :— ‘ 
“The quantity of soil covering the surface one acre 
is represented by at least 1,600 tons, and with 176 lbs. 
of ammonic sulphate and 354 lbs. of nitrogen—that is 
to say, the one-hundred-thousandth part of the total 
weight of the soil, the crop of wheat will be increased 
from 134 to 163 bushels per acre, and the straw from 
2,640 lbs to 3,520lbs. . 
«‘ With potatoes, 176 lbs. of nitrates, of which 822 are 
in the form of potassic nitrate, suffice to raise the 
yield from 4 tons per acre to 7 tons 4 cwt. 
‘If the manure contains 528Ibs. of calcic phos- 
phate, we shall obtain 32 tons of canesstripped of 
leaves: but with 352lbs. of the phosphate, the result 
is lowered to 16 tons. What result, I ask, obtained 
by purely scientific means, can be compared with this, 
whether as regards the delicacy of the method, or the 
atility of the information that 1t yields. The great 
value of experimental fields, then, lies in our being 
able to obtain such evidence as they latter by a series 
of proofs.” 
- 
ARTIFICIAL MANURES FOR COFFEE. 
In considering the best artificial manures for coffee 
the constituents of sombreorum ought to help us 
largely, for welearnt from Mr. Tytler that this manure 
was based on the result of numerous analysis of every 
part of the coffee tree. Its costliness is the great ob- 
jection offered to sombreorum, and possibly M. Ville’s 
normal manure is a better combination. The question 
here, also, ist one of cost. Results, however, must be 
held essentially to qualify this question of cost. 
Experiments ought, therefore, we submit, to be tried 
with M. Ville’s normal manure, in its complete form, 
and dropping one of the substances in succession. 
We have already said that for such districts as 
Dimbula and Dikoya both nitrogen and potash could, 
for a while, be dispensed with. Where, as is prob- 
ably the case with coffee, calcic phosphate (?) 18 the 
dominant constituent, ‘‘the economical part ef the 
