230 
Canadian Agriculture. 
fertility is unavoidable in the process of bringing these virgin 
soils under profitable cultivation, and the only remedy is to be 
found in increase of population. Still the fact should not be 
lost sight of, that such practices of pioneer settlement do involve 
serious waste of fertility. It mav not be out of place to append 
the opinion of the Rothamsted investigators, that a fertile soil is 
one which has accumulated within it the residue of ages of 
previous vegetation, and that it becomes infertile as this residue 
is exhausted. 
Through the kindness of my colleague, Dr. J. M. H. Munro, 
F.C.S., I am able to give the following complete analysis of, 
and report upon, a sample of prairie soil taken from the first 
12 inches : — 
Analysis of Prairie Soil from Birtle, 2Ianifoha. 
The soil dried at 212° F. contains— 
Organic matter and combined water 
Small stones and gravel 
Gravellv sand 
Fine sand 
9 
70 
1 
41 
O 
45 
G4 
20 
11 
TO 
10 
54 
li 0-00 
Associated in the air-dried soil with — 
Moisture 6 'TO 
The fine earth (passing through a sieve 30 meshes to the inch) dried at 
212° F. con tains- 
Organic matter and combined water .. .. 10 "07 
Pand and silicates 83 "41 
Peroxide of iron and alumina 4" 195 
Carbonate of lime 0"9t3 
Potash (K,0) 0-271 
Phosphoric acid (PoO^) 0-195 
Magnesia (ilgO) .'. 0-487 
Chlorine .. " 0-010 
Sulphuric acid (SO3) trace ' 
2s'ot determined, and loss 0 - 402 
100-000 
Per cent. 
Total nitrogen 0*412 
Total minerals dissolved by cold water .. 0*048 
Potash soluble in water 0-0081 
The sand and gravel of the soil consist chiefly of fragments and pebbles of 
qiaartz, with an admixture of other minerals derived from igneous rocks, and 
here and there a spangle of mica. The black colour is due to vegetablo 
matter, which is present in very large proportion, and is the chief source of the 
great fertility of the soil. A rough measure of this fertility is the percentage 
