THE ELECTRIC TELEGRAPH. 233 



Europe sought "to improve upon the ideas then promulgated. We read of 

 telegraphs constructed at Madrid by Salvaand Betancourt in 1797 and 1798, 

 one extending for more than' twenty miles. The first-named gentleman 

 finally proposed to substitute the Voltaic pile for the usual machine, and 

 Ronalds and Dyar in England and New York respectively employed frictional 

 -electricity with some success. The latter sent charges of frictional electricity 

 through a wire, and they were recorded by being made to pass through 

 litmus paper. The distances between the discharges were intended to indicate 

 the letters of the alphabet, but even if the experiment was fairly tried it 

 failed, for little was heard of the result. 



After the invention of Volta's pile, which Salva wished to adopt, 

 Sommering began his experiments. He used thirty-five wires, set up 

 vertically at the bottom of a glass reservoir of water, and terminating in gold 

 points. These wires ended in the opposite direction in brass plates attached 

 to a bar of wood. At one end the points and at the other the plates bore the 

 same letters respectively; hydrogen at one gold point, and oxygen at another, 

 and two different letters were indicated when the current was sent through 

 any two plates. This arrangement was afterwards improved upon, and only 

 two wires retained. 



It was not until electro-magnetism had been developed, however, that 

 Oerstead found out the power of electricity to deflect the magnetised needle, 

 .and in 1820, Scheweigger added a "multiplier." Then came Arago into the 

 field with his discovery, that a " wire carrying a current could magnetise a 

 steel rod." Ampere substituted a helix for a straight wire, and Sturgeon used 

 soft iron for steel, and developed the electro-magnet. Daniell's battery, and 

 Faraday's discoveries of magneto-electricity and the induction coil were the 

 means of putting a constant supply of electricity at the service of the 

 telegraph and so on, till 1830 brought out a more practical method introduced 

 by Schilling. 



In that year Baron Schilling made a telegraph,and exhibited it in 1832 

 at Bonn. This invention, with five vertical needles, was shown to Mr. Cooke in 

 1836. But in 1 834, Gauss and Weber had succeeded in sending signals by 

 means of a voltaic current acting upon a magnetised needle, and this appa- 

 ratus was really the first practical electric telegraph in use, and it was much 

 improved by Professor Steinheil of Munich. They employed a magnetic- 

 -electro machine, and caused a bar to move in certain directions to indicate 

 certain letters of the alphabet. This was really of value, but Steinheil, the 

 pupil of Gauss, assisted by his government, employed only a* single wire, and 

 made the earth complete the circuit for him instead of having a return wire 

 as his predecessors had. This telegraph was perfected by a series of bells, 

 which gave different tones for different letters, and he also caused the needle 

 to make certain tracings as it moved upon a paper slip, something like the 

 Morse pattern, which was completed in 1837. 



Professor Morse, in 1832, conceived the idea of an electric telegraph 

 but his claim was disputed by a Doctor Jackson, who was on the same vessel 



