Stories of Inventors - The Adventures of Inventors and Engineers by Russell Doubleday
page 14 of 140 (10%)
page 14 of 140 (10%)
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commercial service in reporting, for a Dublin newspaper, the events at a
regatta at Kingstown, when about seven hundred messages were sent from a floating station to land, at a maximum distance of twenty-five miles. It was shortly afterward, while the royal yacht was in Cowes Bay, that one hundred and fifty messages between the then Prince of Wales and his royal mother at Osborne House were exchanged, most of them of a very private nature. One of the great objections to wireless telegraphy has been the inability to make it secret, since the ether waves circle from the centre in all directions, and any receiving apparatus within certain limits would be affected by the waves just as the station to which the message was sent would be affected by them. To illustrate: the waves radiating from a stone dropped into a still pool would make a dead leaf bob up and down anywhere on the pool within the circle of the waves, and so the ether waves excited the receiving apparatus of any station within the effective reach of the circle. Of course, the use of a cipher code would secure the secrecy of a message, but Marconi was looking for a mechanical device that would make it impossible for any but the station to which the message was sent to receive it. He finally hit upon the plan of focussing the ether waves as the rays of a searchlight are concentrated in a given direction by the use of a reflector, and though this adaptation of the searchlight principle was to a certain extent successful, much penetrating power was lost. This plan has been abandoned for one much more ingenious and effective, based on the principle of attunement, of which more later. It was a proud day for the young Italian when his receiver at Dover |
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