ADVANCE OF ELECTRICAL SCIENCE

Ashburton Guardian, Volume V, Issue 1584, 14 June 1887, Page 3

ADVANCE OF ELECTRICAL SCIENCE

11 The Times," m a recent Issue, Rives lome details of what was probably the moat remarkable advanoe In eleotrloal lotenoe brought under the notice of the late Mr S. W. M'Gowan, who (s deaoiibed In that journal aa " Director In-Ohief of Telegraphs and Deputy PostmasterGeneral of Australia," daring his travels. It was an lavo&tlon known &■ phon< p'u fa by means of wbloh electrioal effects are produced under conditions which have hitherto been considered impossible. Among other things, telegraph messages can be transmitted and received through an ordinary line wire, while at the same time other telegraphio messages are being transmitted and reoelved through the same wire by the ordinary telegraph apparatus. It will certainly come ts a surprise to many to learn chat the phonophorlo Instruments have no conducting cirouit through them, but (his Is nevertheless a faot. The phouophore gives uninterrupted paiaogo to eleotrloal effeota oapable of being associated with sound, although it do3B not permit the passage of electrlo currents. The experiments conducted m the la'.e Mr M'Gowan's pre3enoe are held to have demonstrated that the phonophore does much more than the ordinary duplexing system can do, for it both duplexes and duplexes the wire — that Is to say, it onablea the wire to carry its two messages either In the same or m the opposite direction*. More than ibis, if the line be already working, either dnp'ex or duplex on the ordinal y system, the phonophore telegraph service oan still be added to It, as if the wire were being used for nothlrg ehe. The pbonophures are exceedingly simple and easy to work. Upon the oooaslon of the trials the ordinary oparator at one station was accidentally absent, and the phonophore telegraph was worked by a lad of sixteen, who had no experience of It. There can be no doubt (says "The. Times") of the practicability of this ingenious system, which, if used m conjunction with existing telegraph systems, would materially Increase their working capacity. In the first of the experiments alluded to a phonophore meuage was transmitted alone from Folkestone to London Bridge, and there received, working a post office universal relay and ordinary Moree .sounder. lathe second experiment a similar phonophore message was transmitted and reoelved while an ordinary telegraph message was travelling <n the tame direction between tho same stations. In the third experiment a phonophore meieage was transmitted and received while an ordinary te'ograph message wes being transmitted la tbe opposite direction between the same stations. In tbe fourth experiment a phonophore message was transmitted and reoelved between the terminal eUtloue while an ordinary telegraph message was •being transmitted between the two inter* mediate stations . In the fifth and last experiment the line wr.3 dhconneotadat London Bridge and Folkestone, so that the ciroo.lt was absolutely broken, yet phonophore messages weie freely exohanged between the' two places. This last service was carried on under ciroum ■tineas In which It w«> Impossible to work the ordinary telegraphs on account of there being no continuous oiroutt In the line.

For continuation of news see fourth page.