the electric and gas properties are united under the one management, which does not find it impossible to push in a friendly and progressive way the use of both illuminants. The most conspicuous example of this identity of interest is given in New York itself. So much for the early opposition, of which there was plenty. But it may be questioned whether inertia is not equally to be dreaded with active ill-will. Nothing is more difficult in the world than to get a good many hundreds of thousands or millions of people to do something they have never done before. A very real difficulty in the introduction of his lamp and lighting system by Edison lay in the absolute ignorance of the public at large, not only as to its merits, but as to the very appearance of the light, Some few thousand people had gone out to Menlo Park, and had there seen the lamps in operation at the laboratory or on the hillsides, but they were an insignificant proportion of the inhabitants of the United States. Of course, a great many accounts were written and read, but while genuine interest was aroused it was necessarily apathetic. A newspaper description or a magazine article may be admirably complete in itself, with illustrations, but until some personal experience is had of the thing described it does not convey a perfect mental picture, nor can it always make the desire active and insistent. Generally, people wait to have the new thing brought to them; and hence, as in the case of the Edison light, an educational campaign of a practical nature is a fundamental condition of success. Another serious difficulty confronting Edison and his associates was that nowhere in the world were there to be purchased any of the appliances necessary for the use of the lighting system. Edison had resolved from the very first that the initial central station embodying his various ideas should be installed in New York City, where he could superintend the installation personally, and then watch the operation. Plans to that end were now rapidly maturing; but there would be needed among many other things--every one of them new and novel--dynamos, switchboards, regulators, pressure and current indicators, fixtures in great variety, incandescent lamps, meters, sockets, small switches, underground conductors, junction-boxes, service-boxes, manhole-boxes, connectors, and even specially made wire. Now, not one of these miscellaneous things was in existence; not an outsider was sufficiently informed about such devices to make them on order, except perhaps the special wire. Edison therefore started first of all a lamp factory in one of the buildings at Menlo Park, equipped it with novel machinery and apparatus, and began to instruct men, boys, and girls, as they could be enlisted, in the absolutely new art, putting Mr. Upton in charge.