p.65

459

of tillage. One principal cause of this abandonment of wheat has been the
diminished yield, an acre only returning twelve to fifteen bushels, or even less;
another is the frequent destruction, or at least material injury to the crop, by
the ravages of insects, by rust, &c.

The former productiveness of the soil would seem to indicate that this defi-
ciency of yield is owing to the exhaustion of some material element by over-
cropping. Deep ploughing will restore the soil in some degree, by bringing
up that which has not been reached by the roots of the plants; but nothing
short of a full restoration from year to year of the exhausted elements, what-
ever they be, will render the yield of wheat permanent and reliable.

Next to rice, wheat sustains more of the human family than any other
grain; and in many respects it is the most valuable. The best varieties are
those that, though small in berry, are fresh, plump, thin skinned, and bright,
slipping through the fingers readily.

Sir John Richardson found wheat cultivated in the "far countries," as far
north as Fort Laird (latitude 60 [degree symbol]5'), where, however, the grain does not ripen
perfectly every year.*

Analysis of wheat of the State of New York; from Emmons' Agriculture
of New York, vol. 2, pp. 144--153:

Winter Spring
wheat, wheat, Straw. Chaff.
grain. grain.

Silica....... 3.525 4.240 49.100 80.60
Silicic acid...... 1.700
Phosphates.... 60.725 67.440 19.600 8.80
Carbonate of lime
Lime....................0.050 3.460
Magnesia..............2.880 0.324
Potash.................. 7.180 14.720 22.245 1.80
Soda....................16.920 3.356 5.195 3.20
Sodium..................0.195
Chlorine................0.295 none 0.121 a trace
Sulphuric acid.......0.895 0.544 0.876 1.21
Organic acids.........2.400
Carbonic acid....not detrmd
Organic matter....... 8.480
Loss.......................3.235 1.200

100.000 100.000 100.921 100.31

*Arctic Searching Expedition, p. 419.