306 Report on the Field and Feeding Experiments at Wohurn. 
of 4 tons per acre, had a very good effect on the permanent 
wheat in 1881. 
On plot 10, manured with 4 tons of good dung, the produce 
amounted to 33"2 bushels, weighing 60 lbs, per bushel, and 
24 cwt, 3 qrs. and 13 lbs. of straw ; whereas in 1880 the pro- 
duce of this plot amounted to only 15"1 bushels, weighing 
50^ lbs. pel bushel, and 19 cwts. 2 qrs. and 3 lbs. of straw. 
Double the quantity, that is S tons, of farmyard-manure per 
acre on plot 11, produced 41-2 bushels, weighing 60 lbs. per 
bushel, and 1 ton 12 cwts. 3 qrs. and 8 lbs. of straw ; the yield 
on the same plot in the preceding year having been only 19f 
bushels, weighing only 51 lbs. per bushel, and 1 ton 5 cwts. 2 qrs. 
and 2 lbs. of straw. 
On plot 6, manured with minerals and about 2^ cwts. of 
nitrate of soda, the produce in corn amounted to 45*2 bushels, 
weighing 60 lbs. per bushel, and 1 ton 16 cwts. 3 qrs. and 
19 lbs. of straw : whilst on plot 8, manured with the same 
minerals and ammonia-salts, containing twice as much nitrogen 
as, in round numbers, the nitrate of soda used on plot 6, 2\ bushels 
less wheat were obtained, and no more straw than on plot 6. 
Without exception the 11 plots produced in 1881 much more 
wheat, in some instances more than twice the weight of wheat, 
and corn of a much better quality than in the preceding year. 
In every instance the application of nitrate of soda in 1881 
had a better result than the corresponding experiments with 
ammonia-salts. The opposite was the case in the preceding 
year, when salts of ammonia, either applied alone, or in con- 
junction with mineral manures, in every instance gave a better 
yield of wheat than the corresponding experiments in which the 
salts of ammonia were replaced by nitrate of soda. 
We have here striking examples presented to us of the danger 
of drawing general conclusions from the harvest-results of a 
single season. Notwithstanding the numerous experiments 
which have been made by many experimenters in which nitrate 
of soda and ammonia-salts have been applied to the wheat- 
crop, we have yet to learn the precise conditions under Avhich 
either nitrate of soda or salts of ammonia produce the larger 
wheat-crop. 
The Experiments on the Continuous Growth of Barley. 
The minerals were sown broadcast on the 12th of March, 1881. 
The dung, estimated to contain nitrogen equal to 100 lbs. of 
ammonia per acre on plot 10, and 200 lbs. of ammonia per acre 
on plot 11, was put on the land in a well-rotted condition on 
the 10th of January, 1881. 
