for Twenty Years in succession on the same Land. 327 
Table XLllI. — Effecta of the Unexhausted Residue of Nitrogen applied to Wheat as 
Ammonia-salts. 
PRODUCE PER ACRE. 
Total Corn in Busheis of 61 lbs. 
Straw (and Chaff). 
Total Produce (Corn and Straw). 
Vbaes. 
Plot B. 
Mixed 
Mineral 
Manure 
alone, 
20 Years, 
,1852-71. 
Plots 
17 or 18. 
Mixed 
M ineral 
Manure, 
every Year 
succeeding 
400 lbs. 
Ammonia- 
salts; 
20 Years, 
1852-'71. 
Plots 
17 or 18, 
over (or 
under — ) 
Plot 5. 
Plots. 
Mixed 
Mineral 
Manure 
alone, 
20 Years, 
1852-'71. 
Plots 
17 or 18. 
Mi.\ed 
Mineral 
Manure, 
every Y'ear 
succeeding 
400 lbs. 
Ammonia- 
salts; 
20 Years, 
1852-71. 
Plots 
17 or 18, 
over (or 
undi-r — ) 
Plot 5. 
Plot 5. 
Mixed 
Mineral 
Manure 
alone, 
20 Y'ears, 
1852-'71. 
Plots 
17 or 18. 
Mixed 
Slineral 
Manure, 
ev( ry Year 
succeeding 
400 lbs. 
Ammonia- 
salts; 
20 Years, 
1852-'7i. 
Plots 
17 or 18, 
over (or 
under — ) 
Plot 5. 
Average, 
8 Years, 
184-1-'51 
1852 
1853 
1854 
1855 
1856 
1857 
1858 
1859 
I860 
1861 
1862 
1863 
1864 
1865 
1866 
18C7 
1868 
1869 
1870 
1871 
1 Bushels. 
311 
25, 
18i 
19f 
19f 
15 
17i 
18J 
215 
17f 
15 
13J 
91 
18| 
151 
19g 
121 
Bushels. 
32 
14| 
8i 
245 
195 
18| 
23 
15, 
191 
19^ 
22| 
i8i 
18 
131 
105 
19| 
16, 
20, 
16 
Bushels. 
Of 
-2^ 
-n 
-Oi 
Oi 
-^ 
31 
OJ 
2i 
li 
^ 
Oi 
3 
— 03 
li 
n 
0? 
-3i 
Cwts. 
281 
i7i 
18i 
22i 
165 
18, 
1 f\ 
145 
14i 
135 
16, 
i5i 
121 
10, 
135 
12 
141 
125 
125 
CwU. 
29S 
15i 
175 
21i 
165 
17i 
17i 
15, 
15^ 
18, 
17 
13| 
135 
13, 
11 
14i 
155 
121 
161 
Cwts. 
1 
-2i 
-Oi 
-1 
Oi 
-Oi 
^8 
31 
ni 
"5 
1 
I5 
2 
Ib 
li 
21 
Oi 
ll 
2| 
Oi 
0| 
3i 
lbs. 
5,122 
3,019 
2,640 
4,007 
2,960 
3,274 
0,10/ 
2.795 
0 , DOO 
2,539 
2,616 
2,960 
3,017 
2,462 
2,091 
2,303 
1,613 
2,481 
2,543 
2,564 
2,207 
lbs. 
5,280 
2,621 
2,534 
3,917 
3,059 
3,111 
3,393 
0, DOO 
2,678 
2,906 
3,248 
3,290 
2,654 
2,568 
2,328 
1,893 
2,807 
2,705 
2,628 
2,797 
lbs. 
158 
-398 
-106 
-150 
99 
-163 
598 
139 
290 
288 
273 
192 
477 
25 
280 
326 
162 
64 
590 
Total .. 
349 
365^ 
16i 
2993 
3215 
225 
54,921 
58,385 
3464 
Average 
m 
18i 
Of 
15 
165 
^ 
2,746 
2,919 
173 
whereas, when the same amount of ammonia-salts was used for 
6 years in succession for barley, there was an excess of produce, 
doubtless due to the unexhausted residue of nitrogen, which 
averaged 2| bushels of corn, and 2f cwts. of straw, per acre per 
annum, for 10 years in succession, with evidence that the effect 
was not even then at an end. 
Thus, it was shown in Sections II. and III. that a given 
amount of nitrogen in manure yielded more increase of barley 
than of wheat in the years of its application ; and it is now seen 
that it also leaves a more effective residue when applied for 
