Transatlantic wireless telegraphy was an accomplished fact.
Though many doubted that an actual signal had been sent across the Atlantic, the scientists of both continents, almost without exception, accepted Marconi's statement. The sending of the transatlantic signal, the spanning of the wide ocean with translatable vibrations, was a great achievement, but the young Italian bore his honours modestly, and immediately went to work to perfect his system.
Two months after receiving the message from Poldhu at St. Johns, Marconi set sail from England for America, in the Philadelphia, to carry out, on a much larger scale, the experiments he had worked out with the tug three years ago. The steamship was fitted with a complete receiving and sending outfit, and soon after she steamed out from the harbor she began to talk to the Cornwall station in the dot-and-dash sign language. The long-distance talk between ship and shore continued at intervals, the recording instrument writing the messages down so that any one who understood the Morse code could read. Message after message came and went until one hundred and fifty miles of sea lay between Marconi and his station. Then the ship could talk no more, her sending apparatus not being strong enough; but the faithful men at Poldhu kept sending messages to their chief, and the recorder on the Philadelphia kept taking them down in the telegrapher's shorthand, though the steamship was plowing westward at twenty miles an hour. Day after day, at the appointed hour to the very second, the messages came from the station on land, flung into the air with the speed of light, to the young man in the deck cabin of a speeding steamship two hundred and fifty, five hundred, a thousand, fifteen hundred, yes, two thousand and ninety-nine miles away—messages that were written down automatically as they came, being permanent records that none might gainsay and that all might observe.
To Marconi it was the simple carrying out of his orders, for he said that he had fitted the Poldhu instruments to work to two thousand one hundred miles, but to those who saw the thing done—saw the narrow strips of paper come reeling off the recorder, stamped with the blue impressions of the messages through the air, it was astounding almost beyond belief; but there was the record, duly attested by those who knew, and clearly marked with the position of the ship in longitude and latitude at the time they were received.
It was only a few months afterward that Marconi, from his first station in the United States, at Wellfleet, Cape Cod, Mass., sent a message direct to Poldhu, three thousand miles. At frequent intervals messages go from one country to the other across the ocean, carried through fog, unaffected by the winds, and following the curvature of the earth, without the aid of wires.
Again the unassuming nature of the young Italian was shown. There was no brass band nor display of national colours in honour of the great achievement; it was all accomplished quietly, and suddenly the world woke up to find that the thing had been done. Then the great personages on both sides of the water congratulated and complimented each other by Marconi's wireless system.
At Marconi's new station at Glacé Bay, Cape Breton, and at the powerful station at Wellfleet, Cape Cod, the receiving and sending wires are supported by four great towers more than two hundred feet high. Many wires are used instead of one, and much greater power is of course employed than at first, but the marvellously simple principle is the same that was used in the garden at Bologna. The coherer has been displaced by a new device invented by Marconi, called a magnetic detector, by which the ether waves are aided by a stronger current to record the message. The effect is the same, but the method is entirely different.
The sending of a long-distance message is a spectacular thing. Current of great power is used, and the spark is a blinding flash accompanied by deafening noises that suggest a volley from rifles. But Marconi is experimenting to reduce the noise, and the use of the mercury vapour invented by Peter Cooper Hewitt will do much to increase the rapidity in sending.
After much experimenting Marconi discovered that the longer the waves in the ether the more penetrating and lasting the quality they possessed, just as long swells on a body of water carry farther and endure longer than short ones. Moreover, he discovered that if many sending-wires were used instead of one, and strong electric power was employed instead of weak, these long, penetrating, enduring waves could be produced. All the new Marconi stations, therefore, built for long-distance work, are fitted with many sending-wires, and powerful dynamos are run which are capable of producing a spark between the silvered knobs as thick as a man's wrist.
Marconi and several other workers in the field of wireless telegraphy are now busy experimenting on a system of attunement, or syntony, by which it will be possible to so adjust the sending instruments that none but the receiver for whom the message is meant can receive it. He is working on the principle whereby one tuning-fork, when set vibrating, will set another of the same pitch humming. This problem is practically solved now, and in the near future every station, every ship, and each installation will have its own key, and will respond to none other than the particular vibrations, wave lengths, or oscillations, for which it is adjusted.