PHOTOGRAPHING THE HUMAN VOICE.

Taranaki Daily News, Volume L, Issue 59, 25 March 1907, Page 4

PHOTOGRAPHING THE HUMAN VOICE.

A wonderful instrument thai pliulographs tho human voice has been invented by two Frenchmen, MM. Pollak and Virag. It "was developed by the inventors at t liesuggestion ol Professor Moragr, of the Sor bonne, from a telegraphic system "which they had produced capable of transmitting 40,000 words an hour. in the rapid system of telegraphy the message is in tin, l form of perforations in afttrip of paper, through a special transmitter, a,nd the perforations determine the intervale between the currents. These intervals are recorded in the receiver by a small mirror, which oscillates in accordance with them. This? oscillating mirror reflects a dancing rav of light from a lamp placed in front of it, and its movements are recorded by an instiument which photographs them on a strip of sensitised paper, which is print and negative in one and which produces the message in an angular upright script. For photographing tlk> voice a microphone is substituted for the transmitter. Hie vibrations cauft:. the mirror in the receiver to oscillate, and the tones are rcpToduo.d on the paper in such a way as to indicate the qualify of the t>"ngor or oivitor—black and strong for the strong voice or email and fin*j for a weak one. The utility of this invention is that ft professor of singing will be able to tell accurately iiow his pupil's voice is progressing by making photographs of it periodically, and the "tono camera" can also be made of great use in the preparation of phonographic records.