h was natural gas. When, after a few years, the natural gas
was all gone, the miller began to use coal, and he still uses
coal--hundreds of tons of it--while the water which once turned the
wheels, runs idly over the falls. This is an example of wholly useless
waste of coal, and just such waste is to be found in hundreds of places
in our country.

If wise mining methods be put into operation, if proper care be taken in
its use, particularly in manufacturing, if the low-grade coals be
utilized, and if other power be substituted wherever practicable, there
need be no question of shortage. There is enough coal in the ground, if
used rightly, to last for ages to come. But because we have wasted vast
quantities of it in the past, and are still wasting it, so that if the
same conditions continue we can distinctly see the end in sight, it is
important that every one understands what these conditions of use and
waste are, and how the abuse may be corrected, so that mine owners and
consumers may all work together to preserve this most necessary
resource.

REFERENCES

Coal is King. Hewette.

Economical Burning of Coal Without Smoke. Bement.

Coal and Coal Mines. H. Green.

International Library of Technology. Vols. 37 and 38.

Reports of Geological Survey.

Report National Conservation Commission.

Conservation of Mineral Resources. (U. S. Report.)

Production of Coals in the U. S. in 1908. Advance chapters available.

CHAPTER VI

OTHER FUELS

WOOD

Wood, which was formerly the only fuel used in this country, has now
largely given place to other fuels. In rural districts and in lumber
regions it is still used extensively; but in the cities, larger towns,
and manufacturing regions, it is not used in commercial quantities. Its
use for power production is limited to the wood-working factories which
have a large amount of waste lumber and which employ this by-product to
furnish heat for steam boilers.

The wood used for fuel or for power usually represents what would
otherwise be lost, the dead trees and the unmarketable timber of the
farmer's wood-lot, the refuse of lumber regions or the waste of
wood-working factories. So that the use of wood as fuel now generally
means the conservation of our coal supply, and a use for the low-grade
parts of the forest.

In some cases, however, farmers cut for fuel fine young trees that
would grow into excellent timber. Liberal planting of trees so that wood
shall