Marconi’s most audacious early ambition was to send a radio signal across the Atlantic. It was generally believed that the curvature of the earth made this impossible, since it the waves were expected to travel in straight lines and could not pass through the earth.
Two wireless stations were set up in 1901: a transmitter of unprecedented power at Poldhu in Cornwall and a receiving station at St John’s in Newfoundland, where the aerial was to be raised by a balloon or a kite. Marconi and his assistants George Kemp and Percy Paget arrived in Newfoundland in
December and, although the balloons failed and one of the kites was blown away, after an anxious wait they finally detected the pre-arranged signal from Poldhu. On 12 December they heard the three dots – the letter ‘S’ in Morse – on a telephone wired in series with a sensitive detector.
The signal had been too weak to be printed on tape in the way telegraphic messages were usually recorded, which led to problems in convincing everyone that the trial had succeeded. Two month’s later, however, signals were successfully transmitted over 2,000 miles to Marconi on board the Philadelphia, leaving no room for doubt.