340 
MESSRS. J. B. LAWES ARD J. H. GILBERT OR THE RESULTS OF 
ammonia-salts on plot 9. This experiment was made on plot 16, and as in the case of 
the other nitrate plots it did not commence until 1858, so that, as before, we give the 
average results for only 8, 10, and 18 years ; and for comparison those of plot 14 for 
the same periods are again brought forward. 
Table XIV.—Average, per acre per annum, by 275 lbs. Nitrate of Soda, with Mixed 
Mineral Manure, containing Potass ; Plot 16. 
.Average per acre per annum. 
Plot 14. 
Mineral manure 
and 550 lbs. 
nitrate soda. 
Plot 16. 
Mineral manure 
and 275 lbs. 
nitrate soda. 
Plot 16 
+ or — | 
plot 14. 
Hat. 
lbs. 
lbs. 
lbs. 
First period, 8 years, 1858-1865 . 
5944 
5058 
- 886 
Second period, 10 years, 1866-1875 . 
6777 
5332 
-1445 
Total period, 18 years, 1858-1875 . 
6407 
5210 
-1197 
Second period, per cent. + or — first period . 
+ 14-0 
+ 5-4 
Ritrogen. 
First period, 8 years, 1858-1865 . 
67-6 
63-0 
- 4-6 
Second period, 10 years, 1866-1875 . 
70-6 
62-4 
- 8-2 
Total period, 18 years, 1858-1875 .. 
69-3 
62 "6 
- 6-7 
Second period, per cent. + or — first period . 
+ 4-4 
-1-0 
Mineral Matter (Ash). 
First period, 8 years, 1858-1865 . 
357-2 
320-9 
- 36-3 
Second period, 10 years, 1866-1875 . 
373-2 
307-9 
— 65 - 3 
Total period, 18 years, 1858-1875 . 
366 1 
3137 
- 52-4 
Second period, per cent. + or — first period . 
+ 4-4 
-41 
There was no plot with the mixed mineral manure and ammonia-salts in quantity 
containing only as much nitrogen as 275 lbs. of nitrate of soda. The main comparison 
must, therefore, be made with double the amount of nitrate (plot 14). 
As with the double so with the single amount of nitrate (and the mineral manure), 
there was an average of more produce of hay over the last 10, than over the first eight 
of the 18 years. But, on the other hand, there is not, as there was with the double 
quantity, a greater average annual amount of nitrogen and of mineral matter removed 
over the second period. There was, however, only a slight deficiency ; and, what is 
more remarkable, there is, over the 18 years, an average of only about 6^ lbs. less 
nitrogen annually removed than where the double amount of nitrate, supplying 
annually about 41 lbs. more nitrogen, was applied. 
