Marconi's Historical Message
December 12, 1901, the first
of Marconi’s dreams came true, when his historic message – the letter “S” was sent in Morse from Poldhu,
in Cornwall, England, over a trans-Atlantic path of about 3000 km to St John's, Newfoundland, using a spark transmitter.
This prearranged transmission was received by Marconi with a receiver connected
to a 100 metre long antenna trailed from a kite.
Perhaps we could have a closer look at what Marconi was trying to achieve in
those opening days of the 20th century, and we examine in some detail how he came to make that historic message.
Marconi believed that his first endeavours to prove that wireless signals could
be transmitted, and received, over long distances, should relate to the trans-Atlantic path, and for that purpose a transmitting
station, at the time the most powerful ever built, was constructed at Poldhu, Cornwall, England.
The antenna system consisted of a ring of 20 masts, each about 70 metres high.
Another similar station was erected in Cape Cod, Massachusetts. However, at the end of August 1901, when the antenna construction
at Poldhu was nearly complete, a storm there virtually destroyed what had already been accomplished, and the entire facility
Nevertheless, Marconi organized a substitute emergency antenna, a simpler device
consisting of 60 vertical wires, 60 metres high, connected to a stay stretched between t two masts 60 metres high.
In November 1901, he sailed from Liverpool, accompanied by his assistants, and
reached St. Johns on December 6.
Bad weather hampered Marconi’s experiments in attempting to set up a suitable
receiving system, but he did manage to put up a kite carrying an antenna wire of about 100 metres long. Suddenly, at about
12.30 pm, he heard a succession of three faint clicks on his telephone receiver, corresponding to the three Morse dots of
the letter S. This occurred several times, removing all possibility of doubt that trans-Atlantic transmission had been achieved.
He repeated the experiment on the following day – successfully.
We should note that Marconi's equipment was extremely crude compared with present
day standards – tubes and transistors had not been invented – amplifiers did not exist – no facilities existed
for generating continuous waves. All that was available was equipment for transmitting damped waves by means of irregular
In 1901, Marconi started to set up a network of permanent wireless stations,
specifically for maritime communications, following the establishment of the Marconi International Marine Company in 1900.
His company built stations on the British and Irish coasts, in Belgium, Germany
and in the USA.
By the end of 1901, the British and Italian Navies had adopted Marconi's invention,
and radio telegraphy facilities had been installed in British and foreign merchant ships, and the Cunard liners Luciana and
In 1903, about 12 months after Marconi's historic message, two-way contact was established across the Atlantic.