Agricultural Ckeniistry. 
41)5 
potash, lime, magnesia, and silica contained in the latter. The 
dry organic matter, nitrogen, and mineral matter, are in most 
cases calculated from direct determinations, made on the produce 
of the dilferent plots ; but in any cases where such direct results 
were not attainable, the averages of allied cases have been taken. 
The constituents of ash are, however, in all cases calculated irom 
an adopted average percentage, deduced from a consideration of all 
recorded analyses with which we are acquainted,* taken in con- 
nexion with the analyses of similar ashes made in the laboratory 
at Rothamsted : — 
Table VIII. — Chemical Statistics of three Eotations, constituents per acre 
(lbs.). Entire produce of Swedes (leaves and bulbs) carted off the laud. 
j 1SI8. 
1 
1 1K49. 
1R50. 
ISOl. 
1 Swedes. 
Barley. 
('lover. 
Wheat. 
Rotation 1. — Swedes, uumanured. 
2460- 
3872- 
4325- 
4315- 
64- 
52- 
142- 
57- 
127- 
179- 
417' 
217- 
ll'S 
21-1 
31 -3 
24-6 
33-8 
31-3 
83-5 
33-4 
19-3 
12-6 
12o-2 
1 1-4 
3-3 
7'2 
35-5 
7 ' 2 
2-0 
92-1 
12-5 
125-8 
Rotation 2. — Swedes, by Superphosphate of Lime. 
Dry organic 
Nitrogen 
i\Iineral 
Phosphoric acid . 
Potass 
Lime 
Magnesia . . 
Silica* 
3945- 
2810' 
4450 
4583 
98- 
38- 
146 
CO 
228' 
129* 
429 
23i 
20-7 
lG-0 
32 
0 
26 
7 
61-0 
22-8 
85 
9 
30 
5 
34 4 
8-8 
128 
8 
12 
4 
5-9 
5-3 
36 
5 
9 
3.7 
65-3 
12 
9 
137 
9 
Rotation 3. — Swedes, by mixed Manures. 
4984 
3269 
5164 
4520 
139 
45 
170 
59 
227 
145 
493 
2S4 
Phosphoric acid 
19 
9 
17 
8 
37 
4 
25 
G 
58 
3 
25 
C 
99 
7 
35 
G 
Lime 
36 
9 
10 
0 
149- 
5 
12 
2 
6 
« 
6 
0 
42 
3 
6 
3 
7 
73 
8 
14 
9 
130 
* la some casjs sml is obviously ii:chidcd with the "silica.'' 
2 K 2 
