This is not very exciting news to men whose time is consumed in the engrossing occupation of earning a living; but scientific facts have a curious habit of lurking in the background, sometimes a long while, and then suddenly stepping up to the footlights in the form of facts or inventions of a kind that are exceedingly important,--even from the standpoint of making a living, or at least of enduring the conditions of living. The study of electrons, for instance led the way to the discovery of the beneficent X-rays, made in 1895 by Röntgen. The first electric railways, like the first railways of any kind, were laid in mines; for the superiority of electricity over steam for use in the unventilated spaces of mines was obviously greater than in the open spaces on the surface. The first one was in the mines at Zankerode in Germany and was constructed by the famous Siemens Brothers. The first electric surface railway was built at Berlin in 1879. It was about three hundred and fifty yards in length, and laid upon wooden sleepers; an auxiliary rail being fixed midway between the two main rails. The auxiliary rail carried the electric current, which was taken off by a brush connected to the electric motor on the car, from which it went to the rails that acted as the "return." The similarity between this system and that now used in all our cities is striking, and shows how practically and scientifically good the first electric railway was. To estimate correctly the influence of the invention of the electric railway would be, of course, impossible, especially on partially developed countries; for the electric railway assisted greatly in developing them. It seems possible, however, that the electric railway may be of not very long life, for the reason that the internal-combustion-engine possesses the same great advantage of smokelessness that the electric motor does and makes possible the use of a much simpler system than electric railways necessitate. The fact that any invention is displaced by a later one does not, of course, detract from the merit of the invention displaced, in having supplied the needed stepping-stone for the other one to rise from. In the same year, Foy invented the steam plow, and Lee invented his magazine rifle. In the following year (1880) Blake invented his telephone transmitter, an improvement of a practical character over preceding ones, Greener invented his hammerless gun, and Faure invented his electric storage battery.