r, the the application of caoutchouc for insulation of telegraphic blows with 28-pound sledges were struck on a chilled wheel, ends projecting at a uniform hight, arranged in spiral rows, wires, so as to supersede gutta percha by an altogether sup.- at one of these trials, before the stout smiths… … sirable. ive cylinders, then shaved The patent for this device is from the periphery by keen dated Dec. 4, 1866, and was obtained cutting machines into very through the Scientific American Patent Agency for Franklin thin long sheets, next slit into tapes,and these are served a piece; as many more…
Internet Archive · Public domain (published before 1931). Free to use for anything.
