PHOSPHORUS FOR SOILS. 179 
Practically speaking, all such pastures will yield a profitable 
return to a suitable application of manures, and in some cases 
the natural yield may be even trebled. 
Attention was first directed to the improvement of pasture 
Jjand by Dr. Somerville, while director of the Northumberland 
County Farm at Cockle Park. His experiments were started in 
1897, and the results to date are published in a report by his suc- 
cessor, Prof. Gilchrist. The plots receiving different manurial 
treatment are each 3 1-20 acres—three acres being grazed each 
summer, while the odd fraction is cut for hay. The live-increases 
of the sheep and the yields of hay are carefully noted during 
each year, and compared with the unmanured plot. Ten differ- 
ent systems of manuring were contrasted in the experiments, but 
the following four only need be referred to, as they were most 
profitable of the various methods: 
Mutton Profit Hay 
PLOT. MANURES. tek produced | from | per acre 
*) (6 years). |manures| (6b years) 
6 MMA NWTET ss e6. geri oeteasiads » ae eibes 246 lbs. iets 59 cwt. 
3 lOCwt. Slag, IN icc cv eees oe 223: 822 lbs. 158s. | 164 ewt. 
4 5 ewt. slag,* 1887, same 1900... 2s 662 lbs. 108s. | 133 ewt. 
5 7 ewt. super,* 1897, same 1900. 86s: 642 lbs. 88s. | 4 cwt. 
8 Sameas plot 5: 3§ ton groun , 
TS9G, SMMC TAOW sess: Kaeg Bae narra 56s. 769 lbs. 107s. | 138 ewt. 
*Containing 100 1bs. phosphoric acid. 
The profit is estimated from the extra mutton produced over 
and above that on the unmanured plot. It is valued for the 
purpose at 3°.d. per pound, live weight. 
Basie slag here has proved at once the cheapest and most 
profitable form of fertilizer on pasture. Its superiority to super- 
phosphate (Plots 4 and 5) seem to be due to the fact that besides 
containing easily available phosphate it also contains free lime. 
Comparison of plots 5 and § bears this inference. The land at 
Cockle Park is stiff clay, and has been under pasture for over 
thirty years. 
Basic slag is purchased on its percentage of phosphate of 
lime. The quality varies from about 20 to 45 per cent phosphate 
(equal to 9 to 21 per cent phosphoric acid). The higher grades 
are usually rather cheaper per unit. The unit prices of different 
samples may be ascertained by dividing the prices per ton by the 
percentages. Other things being equal, the quality which sup- 
plies the unit of phosphate at the lowest cost on the farm should 
be purchased. 
I devote this amount of space to basic slag be- 
