8 APRIL 1899, Page 13

WIRELESS TELEGRAPHY.

[To THE EDITOR OP THE "SPECTATOR."] SER„—I notice in the Spectator of April 1st, a propos of wire- less telegraphy, the remark : " If the ether can transmit vibration in a guided direction, it can also, transmit sound." May I point out that under the present system, electric waves are propagated in all directions from the transmitting instru- ment, and are not " guided " / A message would be received at every place within the limiting distance, if . only a " receiver " were there to be affected by the waves. "Secondly, vibrations which give lise to 'round, occur only in the air, and by no possibility could ether disturbances have any audible effect.—.- I am, Sir, &c., PHILIP HARRISON. 1? Weech Road, W. Hampstead.