but, nevertheless, his announcement had been verified in all but the question of cost. The introduction of a practical system of electric lighting employed his resources for several years. Dynamos, types of lamps and conductors, electric meters, safety fuses, and other appliances had to be invented. In 1882 he returned to New York, to superintend the installation of his system in that city.
His researches on the dynamo caused him to devise what he calls an 'harmonic engine.' It consists of a tuning-fork, kept in vibration by two small electro-magnets, excited with three or four battery cells. It is capable of working a small pump, but is little more than a scientific curiosity. With the object of transforming heat direct from the furnace into electricity, he also devised a 'pyro-electric generator,' but it never passed beyond the experimental stage.
The same may be said for his pyro-electric motor. His dynamo-electric motors and system of electric railways are, however, a more promising invention. His method of telegraphing to and from a railway train in motion, by induction through the air to a telegraph wire running along the line, is very ingenious, and has been tried with a fair amount of success.
At present he is working at the 'Kinetograph,' a combination of the phonograph and the instantaneous photograph as exhibited in the zoetrope, by which he expects to produce an animated picture or simulacrum of a scene in real life or the drama, with its appropriate words and sounds.
Edison now resides at Llewellyn Park, Orange, a picturesque suburb of New York. His laboratory there is a glorified edition of Menlo Park, and realises the inventor's dream. The main building is of brick, in three stories; but there are several annexes. Each
