316 
MESSRS. J. B. LA WES AND J. H. GILBERT ON THE RESULTS OF 
6. Mixed Mineral Manure, with, and without, Potass; Plot 8. 
In the next table are compared the results obtained by mixed mineral manure alone 
in both cases, but in one including and in the other excluding potass. During the 
first six years of the experiments (1856-61) plots 7 and 8 each received the “mixed 
mineral manure/’ comprising superphosphate of lime, and sulphates of potass, soda, 
and magnesia, the only difference being that during those years, and in 1862, plot 8 
also received 2000 lbs. of sawdust per acre per annum. From 1862 inclusive up to 
the present time, plot 7 has continued to receive the same mixed mineral manure, and 
plot 8 the same, excluding the sulphate of potass, but with an increased amount of 
sulphate of soda. The table shows the results yielded on the two plots, over the first 
six years, during which (with the exception of the sawdust on plot 8) both were manured 
alike, over the next 14 years, when the only difference was the omission of the potass 
and increase of the soda on plot 8, and over the total period of 20 years, 1856-1875 
inclusive. 
Table VIII.—Average, per acre per annum, by Mixed Mineral Manure, with and 
without Potass; Plots 7 and 8. 
Average per acre per annum. 
Plot 7. 
Mineral manure, 
including potass, 
every year. 
Plot 8. 
Mineral manure, 
including potass 6 years, 
without potass 14 years. 
Plot 8. 
1 + or — plot 7. 
Hat. 
lbs. 
lbs. 
lbs. 
First period, 6 years, 1856-1861 . 
3835 
4027 
+ 192 
Second period, 14 years, 1862-1875 .... 
4011 
3098 
-913 
Total period, 20 years, 1856-1875 .... 
3958 
3377 
-581 
Second period, per cent. + or — first period . 
+ 4-6 
-23T 
Nitrogen. 
First period, 6 years, 1856-1861 . 
56-6 
60-9 
+ 4-3 
Second period, 14 years, 1862-1875 .... 
56‘6 
40-3 
-16-3 
Total period, 20 years, 1856-1875 .... 
56-6 
46’5 
-10-1 
Second period, per cent. + or — first period . 
o-o 
-33-8 
Mineral Matter (Ash). 
First period, 6 years, 1856-1861 . 
254-4 
271-8 
+ 17-4 
Second period, 14 years, 1862-1875 .... 
253-7 
181-9 
-71-8 
Total period, 20 years, 1856-1875 .... 
253-9 
208-8 
-45-1 
Second period, per cent. + or — first period . 
-0-3 
-33T 
