LONG DISTANCE TELEPHONY.

New Zealand Herald, Volume XLVIII, Issue 14690, 26 May 1911, Page 8

LONG DISTANCE TELEPHONY.

A NEW INVENTION.

REMARKABLE IMPROVEMENTS.

Long-I)istan'CTs telephony has been regarded in Now Zealand, until recently, as too expensive a privilege to be made cheap find popular, because it meant the installation of a double line of heavy copper wire between the talking points. A demonstration of the newest, form of long.distanco telephone at a lecture in the Wellington railway social hall by Mr. J. T. Fahy, A.M.1.E.E., showed that it is possible not only to hold audible and easy conversation with a person at Palmerston North (a distance of about 90 miles) but also to transmit telegraphic messages simultaneously over the same wire.

The I'honofor, as the instrument is christened, is of English origin, and the first set imported into New Zealand came through the agency of Mr. J. H. Wynne, electrical signal engineer to the New Zealand Railways Department. A trial has been made with it between the chief traffic j inspector's office in Wellington and Palmer- j stem North railway station. Telephonic, conversation over that distance had previously been almost impossible— quite unreliable for business purposes — because of the many interruptions from other points in the circuit, and the tremendous buzzing duo to induction. Now, to use the simile of one of the officers with experience of its working, " Giving orders to Palmerston is as easy from Wellington as if you were looking in at the door." All tho time the line is in use for telegraphing of Morse signals, which are not heard through the telephone. Roughly speaking, it costs about £1000 to put in a copper wire for telephoning between Wellington and Palmerston North, but the Phonofor gives far better talking facilities for the expenditure of £10 on instruments attached to the iron wire of tho telegraph line. A whisper can bo heard at the far end of tho wire, and it was, of course, quite easy for a Palmerston North listener to hear the pianoforte played in the railway social hall in Wellington. The Phonofor has a sound-magnifying attachment enabling tho far-away speaker to make himself audible to a- roomful of listeners. This experiment was tried by .Mr. Fahy last night, a cornet solo being played at the traffic office in Featherstonstreet and easily heard in the hall through the instrument about 100 yards off. Distance, it was explained, is immaterial, at any rate within wide limits. Mr. Fahy gave an admirable summary of the history of electricity, and made a number of interesting experiments with a high tension current. He showed the Rontgen ray,, operated wireless telegraphy, the Wheatston© automatic telegraphing instrument (loaned by the Post and Telegraph Department), and the Kelwin galvanometer, the highly-sensitive instrument used in submarine cabling over long distances, in which the dot and dash of the Morse alaphabet has to be read by a small patch of light travelling over a scale.