at almost all seasons. Do you
understand what that means? It means that this great productive region
is growing poorer each year, and that as the population increases, and
the need of great harvests increases, the land is becoming less able to
produce them. The Mississippi River is said to tear down from its banks
more soil each year than is to be dredged from the Panama Canal. At the
mouth of the river is a delta many miles in extent, formed wholly of
land that has been carried down the river. The soil in lower Mississippi
and Louisiana is almost black, and is in many places seventy feet in
depth, and it has all been left there by the river, which took it from
the higher lands.

It is estimated that our rivers carry out to sea one billion tons of our
richest soil each year. The ancient Egyptians worshiped the Nile because
each year the spring floods left behind the rich soil deposits that
fertilized their fields and gave them an abundant harvest. Entire fields
and even whole farms along the upper stretches of the Mississippi and
Missouri have been carried away, not the top soil only, but the land
itself, by the swift current of the springtime floods as they cut a new
channel for the river.

Canaan, the "land of promise" of the Bible, was once an abundant region,
"flowing with milk and honey" in the language of Moses, with its grapes,
its vast forests of cedar, fir, and oak, its treasures of wheat,
olive-oil, and other rich agricultural products. Now all are gone. The
entire country seen by the traveler in the Holy Land to-day is one of
the most desolate regions on the globe, where the few inhabitants are
scarcely able to obtain a scanty living.

We wonder what has brought about this change, and we have not far to
seek in answer to our questioning. The preservation of the forests means
the preservation of the soil, and the destruction of the forests means
the destruction of the soil. This is the universal law. First the
forests were cut down and the hillsides left bare. Then the streams wore
great ravines down the unprotected hillsides. Steadily the work of
destruction by erosion has gone on, until time beyond our possibility to
comprehend must pass before the land can be made productive again. The
hills and valleys of China have been devastated in the same way, and
many of the older regions of the earth that were once the sites of great
cities and extensive commerce are now marked only by the ruins of the
civilizati