On the Rain and Drainage - Waters at Rothamsted. 51 
Table LI. — Nitrogen supplied in Manure, recovered in the 
Crop, and in the Drainage, and unaccounted for in either Crop or 
Drainage, in the Experimental Wheat-field. 
Two Yeaes. Quantities in Lbs. per Acre. 
Nitrogen per Acre per Aunum. 
In 
Manure. 
15 
16 
Unmanured continuously . . 
Mixed Mineral Manure 
Mixed Min. Man. and 200 Ibs.l 
Ammonium-salts . . . . / 
Mixed Min. Man. and 4001bs."» 
Ammonium-salts . . . . / 
Mixed Jlin. Man. and 600 Ibs.i 
Ammonium-salts . . . . / 
Mixed Min. Man. (on half)) 
and 550 lbs. Nitrate Sodium/ 
400 lbs. Amm. -salts, alone . . 
400 lbs. Amm. -salts and Su-'l 
perphosphate | 
400 lbs. Amm. -salts, Super-1 
phos., and Sulph. Sodium / 
400 lbs. Amm. -salts. Super- 1 
phos., and Sulph. Potass.. | 
400 lbs. Amm. -salts, Super-i 
phos. and Sulph. Magnesium/ 
400 lbs. Amm. - salts, and'l 
Mixed Minend Manure . . / 
Unmanured, 1865 and since 
0 
0 
44 
132 
86 
88 
88 
88 
0 
Crop. Drainage. D,,7„'^3g^ 
]2 
16 
27 
40 
49 
32 
14 
29 
32 
38 
37 
32 
14 
lbs. 
15 
17 
22 
28 
43 
58 
50 
30 
35 
32 
37 
74 
16 
lbs. 
27 
33 
49 
68 
92 
90 
64 
68 
67 
70 
74 
106 
30 
Un- 
accounted 
for. 
lbs. 
(+ 27) 
(+ 33) 
(+ 5) 
20 
40 
(+ -t) 
24. 
20 
21 
18 
14 
j 
|(+ 18) 
:(+ 30) 
In reference to the quantities of nitrogen supplied by manure, 
it is assumed that the 400 lbs. ammonium-salts supplied 88 lbs. ; 
and they may have supplied nearer 90 lbs. Formerly we 
assumed this quantity to contain only 82 lbs. ; but of late years 
ammonium-salts have occurred in commerce in a state of greater 
purity. The amount of nitrogen contributed by manure ob- 
viously by no means represents the total quantity annually 
available. There will be about 2 lbs. annually supplied in the 
seed ; and there is a considerable quantity, of which we shall 
endeavour to form some estimate further on, annually available 
from the atmosphere by rain and condensation, and from the 
stores in the soil itself. Our present purpose is, however, only 
to call attention to the relation of the amount of nitrogen in the 
crop and drainage to that in the manure. 
It will be seen that in only two cases of spring sowing of 
the nitrogenous manures, Plot 6 with the smallest quantity of 
ammonium-salts, and Plot 9 with nitrate of sodium, did the 
E 2 
