on every hillside acre. A little examination of the facts and careful
inclusion of the time element will show that the old-world saying,
"After man the desert" is quite as true in the United States as in
Europe and Asia, where it has been so fearfully proven in the seats of
ancient empire.

This soil resource destruction from erosion leads to the destruction of
other valuable resources. We appear to be upon the eve of an epoch of
waterway construction and experiment. The greatest injury to waterways
is channel filling by down-washed mud. Pittsburgh has been praised
highly for the energetic action of her Chamber of Commerce and citizens
in appropriating money for the careful survey of drainage basins above
the river, with the idea of obtaining knowledge preparatory to the
building of reservoirs to check floods. They have forty-three reservoir
sites, and the early construction of nineteen of these reservoirs is
recommended.

A part of the reservoir plan, however, is that the land above it shall
not be cultivated; otherwise the erosion from the tilled fields will
promptly fill up the reservoirs, as the present condition of many
eastern mill dams so emphatically attests. The carrying out, therefore,
of the Pittsburgh reservoir plan necessitates the exodus of hundreds of
thousands of farmers and the restriction of many farming communities to
forest or a new type of agriculture.

We cannot spare all this land from tillage. But fortunately, there are
other ways of using it. Land east of the 100th meridian may be divided
into three classes: First, which in the absence of better estimate
covers one third of the area, is hopeless for agriculture because of
hills and rocks. This is mostly now in rather poor forests. The second