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Although the nature of wireless waves was not unknown when Marconi started his experiments; it was he who made practicable the use of their properties. The enormous value and scope of radio transmission to-day has been developed from his brilliant discoveries and untiring research


Guglielmo MarconiANY passer-by at Signal Hill, Newfoundland, on December 12, 1901, might have been excused for thinking that the man to be seen there flying a kite was simply attempting to repeat Benjamin Franklin’s famous experiment of some 150 years earlier.

The two experiments had two things in common. Both were made in the hope of obtaining an electrical discharge from the upper regions of the air, and both were successful. Franklin proved by his kite-flying that the awe-inspiring lightning flash was of the same nature as the spark from the Leyden jar. Marconi showed that an infinitely smaller discharge could be sent across the ocean in a curved path and made to report itself 2,000 miles away. To-day a commonplace radio transmission over such a distance was then considered to be impracticable by so many people that Marconi hesitated for two days after the experiment before he sent a cablegram to England announcing his achievement.

The story of the early days of Guglielmo Marconi is not one of contention with adversity. He was born at Bologna on April 25, 1874. His father was an Italian country gentleman and his mother, to whose faith in him the boy later owed much, was an Irish lady of good family. Nothing notable is recorded of his childhood, nor of his schooldays, save that he was keenly interested in physical and electrical science. His youth was spent at an Italian University and he was 21 before he began to concern himself seriously with what were then known as Hertzian waves.

It is quite wrong to assume, as so many people do, that Marconi discovered “wireless” waves. Long before him the British physicists James Clerk-Maxwell and Sir William Crookes had predicted their existence, and in 1886 the young German Hertz was able to demonstrate it. Sir Oliver Lodge also produced wireless waves, but he used them in demonstrations only, as did some others. Among these were Professor E. Branly, of Paris, who devised the well-known “coherer”, and the Russian, Professor A. Popoff, who first used this device in detecting electromagnetic waves derived from the lightning flash.

Marconi's place in the history of engineering is secured by the fact that his genius enabled him to foresee the possibilities of, and to bring to pass, the harnessing of the waves so that they could be used to convey messages over distances of thousands of miles instead of merely announcing their presence to an apparatus a few hundred feet away.

Marconi, when he turned his attention to the subject in 1895, soon discovered that he must improve the receiving instrument and he set to work on the Lodge-Branly coherer. This he altered until it would transmit sufficient incoming current to operate a relay. Then he invented an automatic tapping mechanism to restore it to the non-conducting condition required for the next set of waves. He had already increased the transmitting capacity of his spark-gap resonator by earthing one of its spheres, an arrangement which had not occurred to his predecessors. He next discovered that the ranges of transmission and of reception were improved by increasing the height of the aerial.

These three inventions were covered by a British patent in 1896, when Marconi came to England and was fortunate enough to secure the interest of the Engineer-in-Chief of the Post Office. This was Sir William Preece, who, years before, had, with A. W. Heaviside, signalled across a space of ten miles, by using parallel telegraph wires, and had performed other notable experiments.

Having been given permission to demonstrate his apparatus at the General Post Office, Marconi speedily proved its efficiency across London. He then did the same thing on Salisbury Plain and across the Bristol Channel. The Italian Government gave him permission in the following year to test the system between Spezia and a warship twelve miles away. Commercial success followed, and a company was formed. By 1901 there were several short-distance transmissions in England, for example between the mainland and the Isle of Wight and installations on the East Goodwin Lightship and the South Foreland Lighthouse, in Kent.

Then came the erection of the station at Poldhu in Cornwall, with its circle of masts each 210 feet high. From this station were sent the historic signals, at first the three dots of the Morse “S”, caught on a kite 400 feet above the ground and 700 feet above the raging sea below the station in Newfoundland. The coherer of filings was later superseded by the crystal detector, which, by allowing waves to pass in only one direction, converts oscillations into pulsations capable of producing audible speech in an ordinary telephone. This in turn was displaced by the thermionic valve of John Fleming and its modification by Lee De Forest and others.

Ennobled by the land of his birth, honoured in countless ways in Great Britain and in other countries, the Marchese Marconi, GCVO, spent a busy and useful life until death came to him on July 20, 1937.

You can read more on “Giant of the Ether”, “Hub of British Broadcasting” and “Making Radio Receivers” on this website.

Guglielmo Marconi