WIRELESS TELEPHONY

Dominion, Volume 7, Issue 2210, 24 July 1914, Page 8

WIRELESS TELEPHONY

CONVERSATIONS OVER 150 MILES

Wireless telephony, it'appears, is at last to enter the. domaiii of practical appliances dwing to an apparatus.' invented by two naval officers, Commander Colin and Lieutenant Jeance. Conversations were carried on at the .beginning of last month over a distiuca of 150 miles, in the presence of representatives of the "Matin" with perfect success, the voice being heard even with greater distinctness than over an ordinary wire telephone. Every tone and inflexion of the speaker's voice was preserved it had been in the sarna rcom. 1 The invention is tho result of fiva years of assiduous lesearch and experiment. : The two officers succeeded 1 in transmitting speech by wireless telephony five years ago, and installed two instruments, in the battleships Verit-e and Justice, but the apparatus was very unreliable owing principally to the varying nature'of the oscillations of the Hertzian waves. This drawback' they succeeded in overcoming by an attachment which acts as a kind of. filter for the waves. The, inventors further state that by slightly varying the respective wave lengths any number of posts can ex-, change conversations without interfering with each other., The apparatus can be used either foiy telephonic or telegraphic purposes, a' facility which will be of considerable importance for military purposes on account of the rigorous accuracy it ensures. While a gaff 150 feet in length will be necessary for long-distance trans-, mission, conversations can bo received by small rudimentary instruments such as.arc used by many private persons ;t« catch tho HiSEel Tower time-signals.