first motor to be tried on real tracks, those of the Edinburgh-Glasgow road, making a speed of four miles an hour. The curse of this work and of all that succeeded it for a score of years was the necessity of depending upon chemical batteries for current, the machine usually being self-contained and hauling the batteries along with itself, as in the case of the famous Page experiments in April, 1851, when a speed of nineteen miles an hour was attained on the line of the Washington & Baltimore road. To this unfruitful period belonged, however, the crude idea of taking the current from a stationary source of power by means of an overhead contact, which has found its practical evolution in the modern ubiquitous trolley; although the patent for this, based on his caveat of 1879, was granted several years later than that to Stephen D. Field, for the combination of an electric motor operated by means of a current from a stationary dynamo or source of electricity conducted through the rails. As a matter of fact, in 1856 and again in 1875, George F. Green, a jobbing machinist, of Kalamazoo, Michigan, built small cars and tracks to which current was fed from a distant battery, enough energy being utilized to haul one hundred pounds of freight or one passenger up and down a "road" two hundred feet long. All the work prior to the development of the dynamo as a source of current was sporadic and spasmodic, and cannot be said to have left any trace on the art, though it offered many suggestions as to operative methods.