Talk:Mathew Evans
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The reference quotes their patent application as having an evacuated bulb with some gas introduced, not specified as, but presumably nitrogen. The carbon is a rod, which is filed to shape, whereas Edison used a true filament of 1/60 inch or so diameter, first of cotton thread, then of bamboo, unlike their patent. Then the Woodward/Evans patent says it is the gas which glows when electricity is applied, unlike in the Edison bulb and today's incandescent bulbs.Either this was some kind of gas discharge or they misinterpreted how it worked. It should be noted that this is similar to bulbs demonstrated and even patented many years before. No reliable evidence is presented that Thomas Edison bought or licensed their patent, or that his bulb derived in any way from theirs, which is just a replication of earlier bulbs which drew too much current and burned out too quickly to be practical. If he was relying somehow on their patent, it would have been prominent in the electric light patent cases which dragged on for many years with numerous false claimants being brought forward and discredited. See more discussion at the Woodward article . They were among dozens of experimenters who tried unsuccessfully to get an incandescent lamp to work from 1802 (Humphrey Davy) to 1879-1880 (Thomas Edison and Joseph Swan). Edison 07:18, 28 April 2007 (UTC)