114 
Some Field Experiments on the 
fed off with sheep. The wheat of 1879 was top-dressed with 
1 cwt. per acre of " concentrated corn-manure " — :but no manure 
was applied in either 1880 or 1881 — except that naturally 
supplied by the sheep consuming the last of the clover in the 
latter part of the season of 1881. 
The two acres of clover ley selected for experiment were 
ploughed up in the early part of October 1881 to a depth of 
about 6 inches. The field was well sampled to about this 
depth, when an analysis of the soil showed it to have the 
following composition : — 
Composition of Experimental Soil, dried at 212^ FaJtr. 
*Oi-c;;inic matter and water of combination .. 7" 444 
Ox'ideofiron 4-940 
Alumina 5 • 800 
Lime • 672 
Magnesia '366 
Potash "482 
Soda -107 
Phosphoric acid '212 
Sulphuric acid "147 
Siliceous matter, &c 79 • 830 
100-000 
* Containing nitrogen "225 
The field having been, as already mentioned, broken up in 
October 1881, was cross-ploughed towards the end of April, 
1882. Between this date and the end of May, it was " culti- 
vated " with a stout drag-harrow three times, and thus pretty 
fairly cleaned from the weeds and twitch that had accumulated 
during the two years' rest. 
On the 1st of June one acre was manured with 10 tons of 
dung, made under cover by sheep fed on cake, corn, and hay. 
After ploughing in the dung, the field was alternately light 
harrowed and rolled about six times. 
The second acre received no dung. 
Each acre was then divided into six equal plots, of which 
two received no artificial manure, two received equal quantities 
of superphosphate (dissolved coprolites), and two received 
equal quantities of ground undissolved coprolites. The super- 
phosphate was put on at the rate of 5 cwts. per acre, and the 
coprolites (very finely ground Cambridge) at the rate of 6i cwts. 
per acre ; this being about an equivalent in money-value for 
ihe 5 cwts, of superphosphate. 
The superphosphate had the following composition : — 
