to exhaust the land, and
led to vast importations of foreign and the manufacture of mineral
manures. I shall not detain you by a discussion of this aspect of the
question, which is of very great moment, consequent upon the removal
of large numbers of people from rural to urban districts; but I may
be excused in saying that agricultural chemistry shows that the
soil--"perpetual man"--contains the ingredients needful to support human
life, and feeding those animals meant for man's use. These ingredients
are seized upon by the roots of plants and converted into aliment. If
they are consumed where grown, and the refuse restored to the soil, its
fertility is preserved; nay, more, the effect of tillage is to increase
its productive power. It is impossible to exhaust land, no matter how
heavy the crops that are grown, if the produce is, after consumption,
restored to the soil. I have shown you how, in the reign of Queen
Elizabeth, a man was not allowed to sell meat off his land unless he
brought to, and consumed on it, the same weight of other meat. This was
true agricultural and chemical economy. But when the people were removed
from country to town, when the produce grown in the former was consumed
in the latter, and the refuse which contained the elements of fertility
was not restored to the soil, but swept away by the river, a process
of exhaustion took place, which has been met in degree by the use of
imported and artificial manures. The sewage question is taken up mainly
with reference to the health of towns, but it deserves consideration in
another aspect--its influence upon the production of food in the nation.

An exhaustive process upon the fertility of the globe has been set on
foot. The accumulations of vegetable mould in the primeval forests
have been converted into grain, and sent to England, leaving permanent
barrenness in what should be prolific plains; and the deposits of the
Chincha and Ichaboe Islands have been imported in myriads of tons, to
replace in our own land the resources of which it is bereft by the civic
consumption of rural produce.

These conjoined operations were accelerated by the alteration in the
British corn laws in 1846, which placed the English farmer, who tried to
preserve his land in a state of fertility, in competition with foreign
grain--growers, who, having access to boundless fields of virgin soil,
grow grain year after year until, having exhausted the fertile element,
they leave it