The first morse code message sent across the Atlantic Ocean by radio, as opposed to cable, was received by Guglielmo Marconi (1874-1937) on 12th December 1901. He was stationed at Signal Hill, near St John’s, Newfoundland, and the signal was sent by a transmitting station at Poldhu, near Lizard Point in Cornwall, England.
Marconi first started experimenting with wireless telegraphy in 1895 in his native
Italy, but moved to in 1896 because he hoped to
attract more interest and support, which was indeed the case. He developed
gradually more sophisticated transmitting and receiving equipment and achieved
progressively greater distances over which signals could be transmitted. England
He was particularly interested in establishing ship-to-shore radio communications, and many of his early experiments were from ships and yachts to receiving stations that he had built onshore. There was clearly a business opportunity here because ships could not be connected by undersea cables in the way that fixed stations could. During the course of these experiments it became clear that radio signals could be picked up even when the transmitter and receiver were not within line of sight of each other, as would be the case when a ship was below the horizon as far as the shore station was concerned. If radio signals could “bend”, what limit could there be to how far they could travel?
Marconi became convinced that it should be possible to send a radio signal for thousands of miles, provided that the transmitting equipment was powerful enough. However, up to this point the best distance achieved had been no greater than about 90 miles (from near
on the French coast to Chelmsford in Essex, where Marconi had established his business
headquarters). Nevertheless, he pressed on with his project to leap the Atlantic.
Work on the transmitting station at Poldhu Cove began in October 1900, the plan being to build a similar station at
, and the work on
this station began in March 1901. Each station was to comprise 20 masts, each
being 200 high, set in a circle that was 200 feet in diameter. In terms of
transmitting equipment, Marconi calculated that the energy needed to send a
signal the required distance would be around 20,000 volts, and this was to be provided
by a Hornsby-Ackroyd oil-driven engine that would drive a 25 kilowatt
alternator and a pair of transformers that would boost the alternator’s 2,000
volts to the necessary 20,000 volts. The final output of the plant, in terms of
signal energy, would be 100 times greater than that of any previously built
transmitter. Cape Cod,
All seemed to be going well until 17th September 1901. By this time the aerials at both Poldhu and
Cape Cod were nearly complete
and Marconi was carrying out tests on the parts of the system that were
serviceable, getting very satisfactory results. However, on that day a storm
blew up and wrecked the circle of masts. This was clearly a massive setback,
but it proved possible to create a temporary aerial, based on only two masts,
that was operational only seven days later. Experiments using this aerial
showed that strong signals could reach Marconi’s station at Crookhaven in , 225 miles away, so Marconi
decided that there was no need to rebuild the station before trying the
ultimate test. County Cork, Ireland
The Newfoundland test
He therefore abandoned the original plan to set up two-way communications between Poldhu and Cape Cod and on 26th November 1901 he set sail, with two colleagues, for
. He had begun to have doubts
about whether the signals would reach as far as Cape Cod and decided to bridge
a shorter distance, St John’s, Newfoundland Newfoundland being the
closest point of the North American continent to . As it happened, just before setting
sail he heard news that the Cornwall Cape Cod station
had also been wrecked in a gale.
The party arrived at
with a quantity of balloons, hydrogen cylinders and large kites, apart from
their portable receiving apparatus. They were received hospitably by the
authorities at St John’s (Newfoundland was a British colony at the time) and
offered space in a disused fever hospital on a rocky promontory overlooking the
town. The appropriately named Signal Hill had been used in past ages for
sending semaphore communications, and was also close to the point at which the
first transatlantic cable had reached shore in 1866. St John’s
The trio tried various methods for getting an aerial wire airborne using the balloons and kites. The winds were strong and at times threatened to be too strong, but, once in place, the kites were perfectly serviceable for what was needed.
The station at Poldhu had been instructed to transmit a morse code “S” (three dots) for three hours every day. This letter was chosen because it would be unmistakable if picked up on the other side of the ocean. Any letter including a dash could be indistinguishable from atmospheric noise.
The first attempts at reception were made on 11th December. Marconi and his team recorded in their notes that something was detected on the Morse detectors, and as clicks on a telephone monitor, but they could not be definite that they were the Poldhu “S” dots.
However, on the following day there was no mistaking the regular three dots. One of the kites broke free, but, when a second kite was raised with a slightly shorter wire, the signals were heard continuously for more than two hours. Marconi was convinced that the experiment had succeeded.
Conditions on later days proved difficult, such that further tests were not possible and Marconi was concerned that his claims would not be believed. In this he was partially justified, because the London press was slow to accept his word for what was a remarkable claim, given the scientific opinion of the time that radio waves could not be “bent” (actually, the waves were being bounced off the ionosphere, but nobody knew that at the time).
Ironically enough, what most convinced people that Marconi had succeeded was the vehemence shown by the Anglo-American Telegraph Company, whose undersea cable had transmitted Marconi’s triumphant massage back to
. They immediately
threatened legal action against Marconi for breaking their monopoly, and
Marconi promptly ended his testing in England . Newfoundland
However, he was clever enough to make public his correspondence with the “Anglo” and won immediate support from the Canadian press and government agencies, the news soon spreading to the
. Many messages of support came his
way, including one from Alexander Graham Bell who made Marconi an offer of land
at Cape Breton, Nova Scotia, for a permanent transmitting/receiving station. United
Marconi packed up his equipment on 23rd December, sending everything back to
one of his colleagues, while he undertook visits to inspect various possible
sites and to meet government officials. England
Before he left
Marconi had a draft contract in his pocket to establish a permanent wireless
telegraph service, and he was promised government finance towards building a
wireless station. Both in Ottawa and New York, Marconi was feted and dined,
being hailed as a hero for his magnificent achievement, although his evidence
for success was extremely sketchy and impossible to demonstrate without a
receiving station being in place. Canada
Fortunately, Marconi had been correct, and later work confirmed what he had claimed. The stations at Poldhu and Cape Cod were quickly rebuilt, with substantial wooden towers instead of flimsy masts, and many technical refinements were to follow.
On 22nd February 1902 Marconi set sail on the SS Philadelphia from Southampton to
, with a view to
sorting out the final details of his Canadian contract. However, he used the
voyage to demonstrate his system to the world at large, by transmitting and
receiving messages as the ship sailed across the New York Atlantic.
The ship’s mast acted as an excellent aerial (albeit much shorter than that
used at Signal Hill) and various improvements allowed for dashes as well as
dots to be received.
The result was that readable messages could be transmitted for up to 700 miles during daylight and more than 1500 miles at night. The three-dot “S” signal could be detected at more than 2000 miles distance. With this very public demonstration the critics were finally silenced.
Marconi’s equipment was to prove its worth in two very notable instances within the following ten years. In July 1910 a radio message to the SS Montrose led to the arrest of Dr Hawley Crippen, who had murdered his wife and attempted to escape to
messages from RMS Titanic in April 1912 led to the saving of many lives due to the
signals being picked up by other ships within steaming distance. Canada
© John Welford