Wednesday, November 21, 2012
His Electrical World magazine article favored silk or cotton thread over steel wire because he didn't think it would be possible "that it would divide itself up properly into a number of short magnets." What he probably meant by that that in being contiguous and ferrous, it couldn't magnetize it in small enough physical increments to make for practical playback. he thought that the tiny currents would cancel each other out. He was wrong, but his idea of coating metal powder on a flexible base is how audio tapes, video tapes, and floppy discs are all made. (Sort of odd we still make all of them isn't it?)
Smith did have the sense to patent the idea in September, 1878, but he never built a prototype. So his article only discussed a theory. While he never made a working model, sources claim he did fabricate a bit of his preferred recording media. He produced a cotton thread which he embedded with steel dust or possibly short clippings of fine wire. It is highly likely he at least attempted to record and playback something prior to publishing but it's impossible to be certain. The IEE raises a similar question in their Smith biography here.
noting that most of his records were later accidentally destroyed.
Smith was born in Cincinnati in 1840, and ran a machine shop in Bridgeton New Jersey with his partner J. B. Webb. Some sources list it's start in 1863, others in 1877. Smith and Webb specialized in making large sheet metal presses to be used by factories to stamp out small objects. But he tinkered too. He patented looms, locks, an automatic garage door opener, an automatic record changers, and other doodads. It was only after his 1880 visit to Thomas Edison’s New Jersey laboratory he began thinking about audio. Edison had recently invented both the phonograph and the microphone.When Smith returned to his shop he began his magnetic experiments.
In the 1898 Valdemar Poulsen proved that Oberlin Smith was right about magnetic recording but wrong about steel wire. Poulsen gave a public demonstration at the Paris Exposition of 1900. Smith became the President of the American Society of Mechanical Engineers in 1899. Fritz Pfleumer followed that up with the first magnetic tape recorder in 1928 fulfilling an Smith's idea, 2 years after his death. More here.