Field Experiments on Potatoes. 
407 
The crop was taken up on the 5th and 6th of October, sorted, 
and each lot carefully weighed by Mr. Hunter, who favoured me 
with the tabular statement of results (Table X., p. 408), showing- 
the kind and amount of manure which was employed on each of 
the manured experimental plots, and giving the produce of the 
ten plots in small, seed, and large potatoes. 
The small potatoes were only fit for pigs, and the others sound 
and of good quality. 
The results of these experiments are in strict accordance with 
those obtained by Messrs. Coleman & Hull, at Escrick, near 
York, with the exception of the produce of the unmanured plots, 
which Avas higher at the farm at Blennerhasset than in the 
Escrick experiments. 
The average produce of the three unmanured plots, calculated 
per acre, amounts to 5 tons 15 cwts., and the dung on an average 
produced 9 tons 1 cwt. and 2 lbs., or an increase of 3 tons, 
6 cwts., and 2 lbs. over the unmanured plots. 
Taking the average produce of the three unmanured plots as 
a basis for calculation, we obtain the following increase per acre 
in each experiment as due to the manures employed : — 
Table IX.- 
-Showing tlic Increase in Potatoes on each Manured Plot, 
calculated to the Acre. 
MAUnRE KMPLOTED. 
I Mineral Superphosphate 
I Muriate of Potash 
( and 
[ Sulphate of Ammonia 
Rotten Dung 
{Mineral Superphosphate 
and 
Muriate of Potash 
I Mineral Superphosphate 
Muriate of Potash 
and 
Nitrate of Soda . . 
Peruvian Guano 
(Mineral Superphosphate 
and 
Common Salt 
Rotten Duna; 
Increase per Acre 
over Unmanured Produce. 
Tons cwts. qrs. lbs. 
3 7 0 16 
11 
10 
12 
0 24 
3 4 
0 I 1 20 
(Decrease) 
2 7 3 8 
Here, as in the preceding trials at Escrick Park, the artificial 
manure, composed of 4 cwts. of mineral superphosphate, 2 cwts. 
ol muriate of potash, and 2 cwts. of sulphate of ammonia per acre, 
gave fully as good a return as 20 tons of good rotten dung. 
Superphosphate and muriate of potash, without sulphate of 
ammonia, produced much less, and the replacement of the 
