trogenous manures can be manufactured electrically at a price far
below the present cost of natural deposits of nitrate of soda. From
the power stations all around the coasts, as well as from those on
waterfalls and windy heights among the mountains, electric cables will
be employed to convey the current for fixing the nitrogen of the air
at places where the manures are most wanted.

The rediscovery of the art of irrigation is one of the distinguishing
features of modern industrial progress in agriculture. Extensive
ruins and other remains in Assyria, Egypt, India, China and Central
America prove beyond question that irrigation played a vastly more
important part in the industrial life of the ancients than it does in
that of modern mankind. This is true in spite of the fact that power
and dominion ultimately fell to the lot of those races which
originally dwelt in colder and more hilly or thickly-wooded regions,
where the instincts of hunting and of warfare were naturally
developed, so that, by degrees, the peoples who understood irrigation
fell under the sway of those who neither needed nor appreciated it. In
the long interval vast forests have been cleared away and the warlike
habits of the northern and mountainous races have been greatly
modified, but manufacturing progress among them has enabled them to
perpetuate the power originally secured by the bow and the spear. The
irrigating races of mankind are now held in fear of the modern weapons
which are the products of the iron and steel industries, just as they
were thousands of years ago terrorised by the inroads of the wild
hunting men from the North.

But the future of agriculture will very largely belong to a class of
men who will combine in themselves the best attributes of the
irrigationist and the man who knows how to use the iron weapon and
the iron implement. As the manufacturing supremacy of the North
becomes more and more assured by reason of the superior healthiness of
a climate encouraging activity of muscle and brain, so the
agricultural prospects of the warmer regions of the earth's surface
will be improved by the comparative immunity of plant and of animal
life from disease in a dry atmosphere. Sheep, cattle and horses thrive
far better in a climate having but a scanty rainfall than in one
having an abundance of wet; and so, also, does the wheat plant when
the limited rains happen to be timed to suit its growth, and the best
kinds of fruit trees whe