Page:Popular Science Monthly Volume 12.djvu/294

280 The life of the locomotive, when well cared for, cannot be exactly stated, but may be taken as not far from thirty years. Repairs cost, annually, ten or fifteen per cent, of the first cost. While running each engine requires about four pints of oil and two tons of coal for each one hundred miles.

71. After their introduction, the growth of railroads and the use of locomotives extended in the United States and in Europe with great rapidity.

The first railroad in the United States was built near Quincy, Massachusetts, in 1826.

In 1850 there were about 700 miles in operation; in 1860 there were over 30,000; and there are to-day about 76,000 miles of completed road in the United States, and the rate of increase had risen in 1873 to above 7,000 miles per year, as a maximum, and the consumption of rails for renewal alone amounts to nearly a half-million tons per year.





HE problem which excites more interest than any other in the larger cities of our country is that in regard to the best disposition of sewage. People have slowly come to realize that in some way a series of disorders arises from the presence of waste matter in cities. So well ascertained is this fact that diseases which are attributed to the presence of filth are aptly called filth-diseases, and it is well that they are at last branded by their right name. One has only to consult the valuable reports of the State boards of health for infomationinformation [sic] on these matters. In these reports he will find an overwhelming mass of evidence tracing typhoid fever, cholera infantum, and other diseases, to the presence of filth, and to its 