Page:Popular Science Monthly Volume 79.djvu/336

332 other hand, the actual poisoning of plants and animals by drainage from industrial establishments attracts much more attention and in many states is forbidden by' law. When there are no longer trout in a once famous fishing stream people are much more likely to notice and to remedy the injury than if sawdust or tailings merely make the stream and its borders unsightly or desolate. In the parts of the west dependent upon irrigation, drainage from mines or works which makes the water poisonous to the crops, arouses the public much more than the pollution which makes it dangerous to drink.

Perhaps it is but natural, and only another exhibition of that modesty which constitutes the distinguishing characteristic of the human species, at all events those influences which affect man and other animals are more likely to be recognized by him than those which affect plants; and those which affect his quick-growing crops, with their more frequent money returns, are more promptly recognized than those which may greatly augment or diminish a harvest coming only twice or thrice in a century. What do we know of the effects of illuminating gas in our houses and gardens, of the effects of the gaseous emanations from domestic and factory fires upon the trees of streets and parks? The only reason why gas-piping is no worse, is that greater leakage would be unprofitable to the gas companies, even at the present high rates. As it is, our houses and laboratories reek of gas to the sensitive nostril, and garden and green-house yield less than they would if the soil were not traversed by badly jointed pipes.

We think and speak of the smoke nuisance as if it were merely a soot nuisance. We do not realize that the most perfect and ideal "smoke consumer," which would certainly lessen our laundry bills, would utterly fail to lengthen life. The most perfect fuels, because the least injurious, are wood and alcohol. How often have we seen a farmhouse overtopped by some great tree and through its branches the fragrant wood-smoke floating gently from the chimney. The substitution of coal for wood would be quickly followed by a succession of troubles which would finally kill the tree, not by "closing its pores" with soot, but by poisoning the living cells in leaves and branches by the sulphur and chlorine fumes given off in burning the coal. So in our towns, you may see holes in what should be domes of foliage, bits of sky through what should be hollow masses of translucent green, olives and yellows when there should be a brilliant verdure. More careful examination will show that not only is the foliage deficient in amount and defective in color in carefully tended city trees, but their annual growth in length and thickness is less than that of their fellows uncared for in the purer air beyond the outmost suburbs. The much advertised "tree surgery" of to-day is a species of not altogether useless quackery, developed to treat a symptom in communities which do not yet