Edison's Inventions

It may be premised that the popular idea that Edison's invention is embraoed in one or two patents is exceedingly erroneous. Before it is absolutely complete, it will probably be covered by thirty, or perhaps forty, patents. Our patent laws do not permit the embracing, in one set of specifications, all the details of a complex plan- each distinct feature must be patented by itself. This was the case with Edison's stock telegraph instrument, which, although uot nearly so complex as the electric liglit, is protected by forty. patents. It was also the case with his automatic system of telegraphy, the patents coyering which number forty-six. His quadruplex telegraph, an apparatus a trifle in comparison with the electric light, so far as minute details are concerned, required for all its parts eleven patents. The various parts of the system of his electric lighting are probably as numerons and require as many patents for complete protection as did the system of lighting by gas, with its puriflers, gasometers, retorts and the hundred other appliances all going to make up the entire plan. Among the appliances of the electric light which will have to be secured, before the light as an entirety can be explained, are the improved dynamo machines, the regulators, condensers, switches and coolers, beside the different portions of the liglit proper and the various forms of conductors and lamps to meet the diversity in the wants of the consumera. When all these are completed - and not a day passes without a marked ad vanee toward their completion- the electric light of the wizard of Menlo Park will oe ready for inspection, criticism and use, but not before.- -New York Herald.