130 
INVESTIGATIONS ON ROTH AMSTED SOILS. 
tion and exercise of function; hence the slowness of soil nitrification 
which, aided by the absence of mineral manure, keeps the crops on 
this plat small, but at the same time renders their decline so remark- 
ably slow that even after more than half a century of ceaseless crop- 
ping, the land still yields from 12 to 13 bushels of grain and its 
accompanying straw per acre. 
The results for the subsoils are more difficult to consider, owing to 
the natural irregularities formerly alluded to. It may, however, be 
said that, in the second depth, from 1865 to 1881 there appears 
throughout to be a diminution of nitrogen, wherever we have 1865 
samples for purposes of comparison. Between 1881 and 1893 the 
general tendency appears to be toward an increase in nitrogen. In 
the third inches, from 1865 to 1881 there appears to be more or less 
decline, with a tendency toward increase between 1881 and 1893. 
But many of the differences are only such as may, so far from the 
surface, be due to chance irregularities. 
NITROGEN AS NITRATES — " NITRIC " NITROGEN (1881 AND 1893 RESULTS 
COMPARED). 
The nitric nitrogen was not determined in 1865, but it was deter- 
mined in the 1881 samples by Professor Warington. The following- 
table shows, side by side, the nitric nitrogen found in the first three 
depths of each plat in both years, and also a summary giving for each 
year the total quantity found in the whole 27 inches. 
Table ^.—Broadbalkirlieat soils, 1SS1 and 1SD3— Nitrogen as nitrates ("mYnc" 
nitrogen) stated as parts per million of fine dry soil and as pounds per acre, 
in samples collected in October, 1S81, and October, 1893. 
First 9 inches. 
Second 9 inches. 
Third 9 inches. 
1881. 
1881. 
1893. 
Plat. 
2a 
2b 
3 
4 
5 
H 
7 
8 
9a 
9b 
10a 
mi, 
11 
12 
13 
14 
15 
16 
17 
18 
19 
12.23 
3.80 
3. 02 
1.94 
(5.46 
:.!»t 
8. 27 
r.r:( 
6.:$8 
5. 56 
.->. 
7.03 
5. 99 
4.94 
6.80 
5. 26 
4. 15 
4. 19 
1 If, 
© 
£ 
O 
Ph 
20.:50 
9. 85 
9.39 
12. 81 
If.. 7;") 
2. /.:>!♦ 
21.44 
20. 04 
16. 54 
11.39 
13.61 
IK. 23 
16.68 
12.81 
16.33 
18. 84 
Hi. 76 
10. KM 
a. 66 
n 80 
9.43 
4.51 
3. 72 
3. 07 
4.00 
5. 45 
6. 77 
6.71 
0.41 
4.28 
i.83 
3.64 
4.50 
5. 46 
5.37 
5. 16 
3. K6 
t 
4.70 
4.49 
8 1 -V) 
co a3 
23.07 
10.53 
9. 64 
7.96 
10. 68 
14.13 
14. % 
L7, H» 
16.62 
LI. 10 
12.52 
9. 1 1 
11.67 
14. 16 
13. 92 
13. 38 
10.01 
L8.69 
12. 19 
11.64 
22.06 
52 
a. 
5.70 
1.94 
1.48 
2. 63 
2. 77 
i. 11 
5. 15 
3.68 
7.43 
4.38 
3. 32 
3.42 
3. K] 
3.3(1 
3.21 
3. '.».") 
1.K6 
2.76 
3. 10 
1.19 
53 
O 
Ph 
15. 23 
5. 18 
3.95 
7.03 
7. 40 
11.14 
13. 76 
9. 86 
19. 85 
11.70 
8.87 
9. 14 
10.18 
8.82 
K 57 
10.55 
L.97 
7.37 
8. 28 
12 . K0 
s a 
Ph 
8.48 
16. 98 
3.45 
2.63 
2. 38 
4.77 
7.19 
10.92 
7.20 
13.05 
it. 52 
10.88 
9.20 
9.54 
9.79 
11.60 
7. 00 
15.94 
10.87 
16.63 
9.12 
co a) 
22.65 
45. 36 
9.22 
7.03 
6.36 
12.74 
19.21 
88. 17 
lit. 23 
34.86 
25. 43 
i io 
24.58 
25.48 
26. 15 
30.99 
18.70 
42.58 
87.70 
41.49 
24.36 
Ph 
2.45 
1.00 
.65 
1.67 
1.71 
2.07 
2. XI 
2.98 
6. H 
2. 65 
2. 15 
1.32 
1 . .58 
.93 
1.31 
1.50 
5.11 
1.24 
1 90 
2. 56 
P. . 
CO CD 
M 
O 
Ph 
.78 
7.90 
8.32 I 
17.98 
7. 10 
6.00 
3.(58 
4.41 
2. (50 
3. (56 
4.19 
14.26 
3.46 
5.30 
7.20 
