Page:Popular Science Monthly Volume 78.djvu/304

294 effects the pecuniary loss from materials lost in smelter smoke may seem unimportant, but measured in dollars and cents it is considerable. Take, for example, bismuth for which there is a steady commercial demand. According to a conservative estimate, in the smoke of the great Washoe smelter at Anaconda there are lost 880 pounds daily. Considering that 10,000 pounds represents the annual American production, it is evident that eleven days would see a waste equal to a year's output of our mines.

Such is the black picture that is painted for us. What of the future? Must the human race abandon a large part of the earth's surface, which it has conquered, because of insufficient means to maintain its bodily warmth? Or must it become a race of troglodytes, dragging out its degenerate existence in the caverns of the earth? Will our agriculture deteriorate, little by little, until the scanty crops from an impoverished soil hardly support a degraded people? Or will the air and water become so polluted that the race, if it be not so modified as to meet the new conditions, must become extinct? Is our boasted civilization only a myth, the growth of which leads inevitably to destruction?

Can our natural resources be so conserved as to supply the immediate and the future needs of the nation? Of what avail is our science which we have so often exalted, and how far can it help us in the solution of this perplexing problem?

We must see that the only conservation which can avail is conservation with utilization, a concept which was clearly set forth by President Taft in his recent St. Paul address:

As we face the problem can we say, as did Patrick Henry, of political questions, "I know of no way of judging of the present but by the past," and, judging by the past, has our science achieved anything which should give us unshakable confidence in its power to meet this crisis? Let us look back into the not too distant past of science for the answer. It comes from many parts of her realm. I may perhaps be pardoned if I draw most of my illustrations from that field with which I am most familiar.

While science has met the demands of the time as they have arisen she does not, as a rule, much anticipate them. It was only after years of extensive working of the saltpeter deposits of South America that in 1889 Sir William Crookes brought home to the civilized world the true significance of the situation—that the supply of combined nitrogen was approaching exhaustion; that this meant the cessation of plant and animal life, and that to avert such a calamity new sources of these compounds must be sought. At the time one means of relief was suggested