108 Experiments icitk different Top-Dressings upon Wheat. 
Table slwwiag the Money Value of the Increase in Corn and Straw per Acre 
over the Unmanured Plot in Experimental Field, and the Clear Profit 
after deducting the price paid for Manures. 
Plot. 
Money Increase in 
Cost of 
nipnr Profif - 
1 op-dressmgs. 
Corn. 
straw. 
JL. 
s. 
d. 
s. 
d. 
£. 
s. 
d. 
4.. 
s. 
,7 
u. 
I. 
(I cwt. of nitrate of sodal 
I and 2 cwt. of salt . . J 
[ 1 J cwt. of nitrate of soda) 
2 
18 
6 
0 
9 
4 
0 
1 7 
0 
2 
10 
10 
II. 
< and 3 cwt. of common | 
3 
15 
0 
0 
12 
2 
1 
G 
3 
1 
8 
III. 
(2 cwt. of nitrate of soda) 
( and 4 cwt. of salt . . j 
4 
14 
6 
0 
14 
7 
1 
14 
0 
3 
15 
1 
IV. 
2 cwt. of nitrate of soda 
4 
13 
0 
0 
18 
9 
1 
10 
0 
4 
1 
9 
V. 
VI. 
3 cwt. of common salt .. 
2 
18 
C 
0 
4 
10 
0 
3 
0 
3 
0 
4 
VII. 
[2 cwt. of Peruvian guano) 
< and 2 cwt. of commons 
1 salt ) 
4 
7 
0 
0 
10 
9 
1 
8 
0 
3 
9 
9 
VIII. 
2 cwt, of Peruvian guano 
4 
4 
0 
0 
14 
10 
1 
6 
0 
3 
12 
10 
genous top-dressings are beneficially applied to wheat grown on 
poor land requires to be accepted with discrimination. If the 
poverty, or rather unproductiveness, is caused by a bad mechanical 
condition and improper aeration of the soil, such top-dressings 
frequently produce marvellously beneficial results, — results, how- 
ever, which jierhaps are not greater than those attending deep- 
ploughing, exposure to air, and similar means for improving 
naturally unproductive clay soils. But if land is unproductive, 
like many sandy soils, simply because it does not contain in 
sufficient quantity all the mineral constituents which enter into 
the composition of the ash of wheat, top-dressings with nitrate of 
soda will tend to its more rapid exhaustion ; and though such 
a dressing may for a season produce a somewhat larger ,corn- 
crop, it is doubtful whether the injury done to the land is not 
greater than the temporary benefit which is realized by the 
crop. 
On the whole, I am inclined not to recommend nitrate of 
soda, as is commonly done, as a top-dressing for wheat on poor 
land, if, as explained, the poverty of the land is caused by a 
d(!ficiency of mineral food ; but I would feel little hesitation about 
using it liberally on clay soils and all land which good culti- 
vation renders productive. Chemically speaking, the better the 
land — that is, the more abundant in it the stores of mineral food 
— the more largely nitrogenous top-dressings may be used, and 
vice versa. 
In concluding this report I liftVO again to express my obligations 
