The Human Ear in Experiment.

Progress, Volume V, Issue 12, 1 October 1910, Page 13

The Human Ear in Experiment.

"To help me to get ideas in approximating the phonautograph to the ear I went to a distinguished aurist in Boston, Mass., Mr. Clarence J. Bake — and he fairly startled me. ' "Why don 't you try a human ear from a dead man as a phonautograph?' he said. 'That's a very interesting suggestion,' I replied. 'I didn't think of such a thing. I should be very glad to get one.'

"He got an ear of some man who had just died, and gave it to me.

"I was then living near Boston, but every summer I used to go for a holiday to my father's residence in Bradford, Canada. Well, I went there that summer of '74 and took the human ear with me. I experimented with it there as best I could away from the facilities which I should have had in the States, and got the most beautiful tracings.

"I was carrying out these experiments so far purely as part of my profession, the teaching of the deaf and dumb in the United States — that is to say, when the dumb existed, for there are no longer dumb in the United States : 75 per cent, are now taught to speak. I had reached the stage of studying the vibrations of the human ear, and I had now got ; a; beautif ul tracing of ' those vibrations.

J . Quite Another Ohaiii. ; l • " Quite apart from those experiments' to help "me hi teaching, I had' also' been engaged for some years on an experiment

in electricity which interested me. I was only an amateur at electricity, but I was very much struck with an idea for transmitting a great many different telegraphic messages over the same wire at the same time. I called it multiple telegraphy. A great many people have been engaged on the same sort of invention, though I am not sure if anything really practical has come of it. I think there were too many people on it. I know I applied for a patent in 1875 and it is not settled yet. My particular idea was to effect it by a transmission of different musical tones. You know that if two pianos are iv the same room, and you strike a particular note on one of them a corresponding string in the other will start vibrating and giving out the same note also. Well, my idea was to invent an apparatus which would be much as if you had two pianos with a great number of electro magnets — one under each string. The stage at which I had arrived in the summer of 1874 was as follows : — Instead of a piano I had a whole row of steel reeds, which were each clamped at one end to the pole of an electro magnet. Each reed was tuned to a different pitch. At the other end of the wire I had a second similar set.

' ' The theory I was working on was that when you have a magnetised steel reed vibrated to and fro in front of an electro magnet you induce corresponding electrical impulses in the coil surrounding the electro magnet. I had a number of these reeds on a number of electro magnets, all connected on the same circuit, but tuned to different pitches. If I plucked one of the reeds it vibrated and emitted a musical tone, and created an undulatory current of electricity in the coil of the electro magnet. This current traversed the wire, and passed through all the electro magnets at the receiving end, causing all the magnets to attract the steel reeds in front of them, and causing that particular steel reed which had the same frequency (that is, which, if struck, would have given out the same number of vibrations) as the one I had plucked at the other end to respond.