CONSERVATION OF NATURAL RESOURCES—DOUGLAS. 325 
recovered annually and goes into commerce as a by-product; for 
the world’s copper may be assumed to carry an average of $10 per 
ton in gold and silver. 
The last application of this mysterious force, by transmitting 
from stationary engines electric current for the movement of trains, 
aims at reducing what is certainly one of the most wasteful uses of 
coal—its consumption in the locomotive for the generation of steam. 
In distributing our coal supply, the railroad burns up from 20 to 25 
per cent of the total production of our coal mines. This will be 
notably reduced, though to what extend has not yet been determined. 
But before this desirable consummation is attained, if electrical 
engineers continue to extend the limits within which long-distance 
transmission can be applied economically, they will bring the latent, 
neglected forces of the whole continent to our doors, and the water 
powers a thousand miles away, as well as the winds and tides, will 
propel our railroad cars as well as heat our houses. The service 
which coal now performs will be fulfilled without the expenditure 
of human labor and the diffusion of so much obnoxious smoke and 
vapor. Long before our coal supplies are exhausted, even on the 
most pessimistic calculation, our children will gladly leave the bal- 
ance in the ground, and charge off to profit and loss some of what we 
now consider our most valuable natural asset. 
There is no doubt whatever that the destruction of our forests is 
attended by a host of such terrible consequences that a halt must be 
called. In the early days at Bisbee, when we were at a distance from 
the railroad, we of necessity almost stripped the hills of their scanty 
clothing of stunted wood, for we were forced to use wood for the 
generation of steam. I find from one of the earliest statements that 
the company burned about 4,000 cords of wood for the year. The hills 
for miles around were completely denuded, with the result that dis- 
astrous floods have ever since almost annually deluged and damaged 
the town, which is built in the troughs of two converging valleys. 
As mining engineers we are sensible of the ruin which reckless lum- 
bering involves, and we lower with regret every stick of timber that 
we bury underground. Nor are we satisfied to bemoan the fact with- 
out making some effort to remedy the evil. It has been suggested, 
and we are trying the experiment, to replace wood by iron. The 
forests can be restored in time by reforestation, but iron ores can 
not be replaced. And, therefore, it is a false economy to attempt to 
save a reproductive material by substituting one which rusts and 
can not be regenerated. Concrete is also being used more and more 
in mining operations, and against its substitution for wood there can 
be no objection; but the most notable economy will result from im- 
proved methods of mining, especially from the introduction of the 
caving and slicing systems. These were introduced into the Cananea 
