Rensselaer Union, Volume 9, Number 48, Rensselaer, Jasper County, 16 August 1877 — Still Another Telephone. [ARTICLE]

Still Another Telephone.

Over a hundred Invited guests witnessed a private exhibition of the “ Edison,” a newly-iavented telephone, In the auditorium of the Main Exhibition Building, last evening. By means of the Instrument vocal and instrumental music performed at ihe Central Station was tram, mitted to the auditorium, where it was reproduced in a louder tone than the original. The Invention is called “ Edison’s Electro-Motograph Telephone." and differs fundamentally from any lnstru ment of the kind which has yet appeared before the public. The transmitting apparatus consists simply of a long tube, having one end covered with a thin sheetbrass diaphragm, kept tight by a stretching ring, and having soldered in the center a thin disk of platinum, immediately in front of which is an adjustable plati-num-pointed screw fixed to a rigid pillar. To transmit the music it is only necessary to hum, sing, or play into the open end of this tube, which action causes the diaphragm to vibrate. The platinum poinls meeting, a circuit is formed, and the eleetrio current transmits every vibration overthe wire to the receiving end. The receiving or reproducing apparatus is based upon an original discovery made by Mr. Edison about fiveyearsago, which was that when a piece of paper is moistened with certain chemical solutions, is laid upon a metallic plate connected with the positive pole of a battery, and a pla-tinum-faced wire connected with the negative pole of the battery is drawn over the paper, the passage of the current through it renders the solution oleaginous, and the wire slides freely over the psper; but when the current is interrupted the normal friction of the paper returns, and the wire slides over it with difficulty. This principle is applied to the receiver—a sounding-board and a drum or wheel having flanges on both sides. Over the drum, which is rotated by a hand-crank, passes a continuous strip of paper, and pressing tightly upon it and the wheel is a smooth platinum point at the end of a spring, secured to the center of the sounding-board. The current from the battery passes to the spring, thence to the platinum point, thence through the moist paper to the drum, and thence back to the battery. When the drum is turned the paper passes forward, and the normal friction between the point and the paper gives a forward motion to the spring also, which draws out one side of the sounding-board. If now a wave of current passes through the paper the friction disappears, and the spring not being pulled, the resonanter regains its horizontal position. This takes place at each vibration. By means of this friction the feeblest current, which would not have any appreciable eftect upon an electromagnet, exerts extraordinary strength. Stretched upon this sounding-board are eight wires, forming the gamut. Any of these will vibrate when the required number of vibrations per second are made by the sounding-board. For instance, mid-*' die C is beard when 256 vibrations are nude per second. The instrument is extremely sensitive, reproduces the highest notes, and overcomes in a great degree the difficulty exnerienced in the use of electromagnets, whose slowness of operation is due to the time required for the magnetization and demagnetization of the iron cores and the production of secondary currents. The reproducing apparatus was on a table in full view of the entire audience. An operator turned the drum crank, and Mr. C. W. Greene announced before each piece of music who was to sing or play it at the Central Station, five miles distant. The reproduction sounded as if coming from a second-rate violin that needed rosin. Ths note could he heard distinctly throughout the largest hall in the city.— Philadelphia Timet. ?y&~