SEA RIDDLES

Dominion, Volume 19, Issue 254, 10 July 1926, Page 22

SEA RIDDLES

WIRELESS BAFFLED BY "BLIND SPOTS’* The zone of silence which, as the “Daily Mail” has recently pointed out, is now believed to be responsible for the many wrecks which have earned for Race Rocks (off the south-east end of Vancouver Island) the gruesome name of the “Graveyard of the Pacific” is not the only sea riddle of the kind that scientists are trying to solve.

Among the most puzzling are the “blind spots” wherein no kind of wireless will work. For some reason as yet unknown, no aerial signals can be passed in these areas. It matters not what kind of apparatus is used or whether high power or low power be employed, the result is the sameabsolute failure, to transmit or receive.

One of the best known of these, “blind spots” lies in the Indian Ocean. When it was discovered, the Admiralty sent a specially equipped vessel and some of the best radio experts in the Navy to try to find the answer to the puzzle. But the puzzle remains. It is the most perplexing of all, though not the only one of the nature. There arc, in fact, so many of them that the Admiralty have fitted up the cruiser Yarmouth for the use of their experimental staff, and she roams the seas gathering data for the information of the naval scientists who.

arc investigating the mysterious vagaries of wireless at sea. Much useful knowledge relative to effect has thus been garnered, though the cause may be obscure. For example, wireless is less reliable within an hour of sunset and an hour of sunrise than at any other time of the day—nobody knows why. Ships arc advised not to use their direction-finding apparatus at these times because of the risk of error.

Similarly ships can obtain wireless “bearings” more accurately by day than by night and high land such as cliffs between transmitter and receiver also causes inaccuracy. The invention of wireless, in short, has revealed that the sea holds many' more mysteries than arc comprised in the talc of missing ships.