Page:Popular Science Monthly Volume 74.djvu/225

neighboring systems and until railway engineers are agreed as to the fundamental questions of frequency and methods of train control it is probable that no large project will be put in hand. A further opposition to be met is the mass of present-day, steam-railway methods and prejudices. The steam railway has a long history and each system has its highly-trained corps of operating engineers. Electrical operation introduces many new points of view, old dangers disappear and new precautions have to be taken. Besides these matters, there are various less important disturbances to steam practise which will have to be provided for, among the most serious of which are the clearances of the third rail and trolley at crossings and at overhead structures; the clearances on draw-bridges and the methods of leading currents through such bridges; new splice bars to accommodate rail bonds and the telltale for notifying a brakeman on top of the car of a low bridge ahead. It seems probable that the next step in this development will be the progressive equipment of a complete system involving through traffic over long distances, with its attendant feeder and branch lines. When such a system is once installed and the minor difficulties above enumerated developed and overcome, a rapid application of electricity for steam operation will follow.