Heroes of the Telegraph [4]
according to the direction of the current. A mirror attached to the suspension magnified the movement of the needle, and indicated the signals after the manner of the Thomson mirror galvanometer. This telegraph, which was large and clumsy, was nevertheless used not only for scientific, but for general correspondence. Steinheil, of Munich, simplified it, and added an alarm in the form of a bell.
In 1836, Steinheil also devised a recording telegraph, in which the movable needles indicated the message by marking dots and dashes with printer's ink on a ribbon of travelling paper, according to an artificial code in which the fewest signs were given to the commonest letters in the German language. With this apparatus the message was registered at the rate of six words a minute. The early experimenters, as we have seen, especially Salva, had utilised the ground as the return part of the circuit; and Salva had proposed to use it on his telegraph, but Steinheil was the first to demonstrate its practical value. In trying, on the suggestion of Gauss, to employ the rails of the Nurenberg to Furth railway as the conducting line for a telegraph in the year 1838, he found they would not serve; but the failure led him to employ the earth as the return half of the circuit.
In 1837, Professor Stratingh, of Groninque, Holland, devised a telegraph in which the signals were made by electro-magnets actuating the hammers of two gongs or bells of different tone; and M. Amyot invented an automatic sending key in the nature of a musical box. From 1837-8, Edward Davy, a Devonshire surgeon, exhibited a needle telegraph in London, and proposed one based on the discovery of Arago, that a piece of soft iron is temporarily magnetised by the passage of an electric current through a coil surrounding it. This principle was further applied by Morse in his electro-magnetic printing telegraph. Davy was a prolific inventor, and also sketched out a telegraph in which the gases evolved from water which was decomposed by the current actuated a recording pen. But his most valuable discovery was the 'relay,' that is to say, an auxiliary device by which a current too feeble to indicate the signals could call into play a local battery strong enough to make them. Davy was in a fair way of becoming one of the fathers of the working telegraph, when his private affairs obliged him to emigrate to Australia, and leave the course open to Cooke and Wheatstone.
CHAPTER II.
CHARLES WHEATSTONE.
The electric telegraph, like the steam-engine and the railway, was a gradual development due to the experiments and devices of a long train of thinkers. In such a case he who crowns the work, making it serviceable to his fellow-men, not only wins the pecuniary prize, but is likely to be hailed and celebrated as the chief, if not the sole inventor, although in a scientific sense the improvement he has made is perhaps less than that of some ingenious and forgotten forerunner. He who advances the work from the phase of a promising idea, to that of a common boon, is entitled to our gratitude. But in honouring the keystone of the arch, as it were, let us acknowledge the substructure on which it rests, and keep in mind the entire bridge. Justice at least is due to those who have laboured without reward.
Sir William Fothergill Cooke and Sir Charles Wheatstone were the first to bring the electric telegraph into daily use. But we have selected Wheatstone as our hero, because he was eminent as a man of science, and chiefly instrumental in perfecting the apparatus. As James Watt is identified with the steam-engine, and George Stephenson with the railway, so is Wheatstone with the telegraph.
Charles Wheatstone was born near Gloucester, in February, 1802. His father was a music-seller in the town, who, four years later, removed to 128, Pall Mall, London, and became a teacher of the flute. He used to say, with not a little pride, that he had been engaged in assisting at the musical education of the Princess Charlotte. Charles, the second son, went to a village
In 1836, Steinheil also devised a recording telegraph, in which the movable needles indicated the message by marking dots and dashes with printer's ink on a ribbon of travelling paper, according to an artificial code in which the fewest signs were given to the commonest letters in the German language. With this apparatus the message was registered at the rate of six words a minute. The early experimenters, as we have seen, especially Salva, had utilised the ground as the return part of the circuit; and Salva had proposed to use it on his telegraph, but Steinheil was the first to demonstrate its practical value. In trying, on the suggestion of Gauss, to employ the rails of the Nurenberg to Furth railway as the conducting line for a telegraph in the year 1838, he found they would not serve; but the failure led him to employ the earth as the return half of the circuit.
In 1837, Professor Stratingh, of Groninque, Holland, devised a telegraph in which the signals were made by electro-magnets actuating the hammers of two gongs or bells of different tone; and M. Amyot invented an automatic sending key in the nature of a musical box. From 1837-8, Edward Davy, a Devonshire surgeon, exhibited a needle telegraph in London, and proposed one based on the discovery of Arago, that a piece of soft iron is temporarily magnetised by the passage of an electric current through a coil surrounding it. This principle was further applied by Morse in his electro-magnetic printing telegraph. Davy was a prolific inventor, and also sketched out a telegraph in which the gases evolved from water which was decomposed by the current actuated a recording pen. But his most valuable discovery was the 'relay,' that is to say, an auxiliary device by which a current too feeble to indicate the signals could call into play a local battery strong enough to make them. Davy was in a fair way of becoming one of the fathers of the working telegraph, when his private affairs obliged him to emigrate to Australia, and leave the course open to Cooke and Wheatstone.
CHAPTER II.
CHARLES WHEATSTONE.
The electric telegraph, like the steam-engine and the railway, was a gradual development due to the experiments and devices of a long train of thinkers. In such a case he who crowns the work, making it serviceable to his fellow-men, not only wins the pecuniary prize, but is likely to be hailed and celebrated as the chief, if not the sole inventor, although in a scientific sense the improvement he has made is perhaps less than that of some ingenious and forgotten forerunner. He who advances the work from the phase of a promising idea, to that of a common boon, is entitled to our gratitude. But in honouring the keystone of the arch, as it were, let us acknowledge the substructure on which it rests, and keep in mind the entire bridge. Justice at least is due to those who have laboured without reward.
Sir William Fothergill Cooke and Sir Charles Wheatstone were the first to bring the electric telegraph into daily use. But we have selected Wheatstone as our hero, because he was eminent as a man of science, and chiefly instrumental in perfecting the apparatus. As James Watt is identified with the steam-engine, and George Stephenson with the railway, so is Wheatstone with the telegraph.
Charles Wheatstone was born near Gloucester, in February, 1802. His father was a music-seller in the town, who, four years later, removed to 128, Pall Mall, London, and became a teacher of the flute. He used to say, with not a little pride, that he had been engaged in assisting at the musical education of the Princess Charlotte. Charles, the second son, went to a village