Vlll PREFA CE. that it may be readily understood by the average reader, and in the hope that it will be instructive and therefore lead to a further investigation of the subject. Thinking it a good plan, he has therefore incorporated the description of the electric locomotive with the book entitled “ Locomotive Mechanism and Engineering,” which has been received so kindly by the locomotive enginemen. It was thought proper to give a descrip¬ tion of the street-railroad and stationary motor as a stepping-stone to the larger motor used on the electric locomotive, since there is no great difference in their principles, but in their size and method of connecting with the axles the method of control is nearly the same. The locomotives which receive their supply of current from a central station and those which generate their own current, and in fact are a travelling central station, are shown. I am indebted to the Electrical World , the Electric Engineer, and the Railroad Gazette for some data and cuts relative to the several electric locomotives shown ; also to the General Electric Company for cuts of their electric locomotive, and others whose apparatus is shown. H. C. Reagan, Jr. Philadelphia, March ist, 1896,
