332 THE POPULAR SCIENCE MONTHLY 



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 depend- 

 ent 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 farm- 

 house overtopped by some great tree and through its branches the 

 fragrant wood-smoke floating gently from the chimney. The substi- 

 tution 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 recog- 



