THE DEVELOPMENT OF ELECTRICAL SCIENCE. 225 



to Gauss and Weber's telegraph, from Poggendorf's Annalen, is of con- 

 siderable historical interest: 



"There is, in connection with these arrangements, a great and until 

 now in its way novel project, for which we are indebted to Professor 

 Weber. This gentleman erected, during the past year, a double- wire 

 line over the houses of the town (Gottingen), from the Physical 

 Cabinet to the Observatory, and lately a continuation from the latter 

 building to the Magnetic Observatory. Thus an immense galvanic 

 chain is formed, in which the galvanic current, the two multipliers 

 at the ends being included, has to travel a distance of nearly 9,000 

 (Prussian) feet. The line wire is mostly of copper, of that known as 

 'No. 3,' of which 1 meter weighs 8 grams. The wire of the multipliers 

 in the Magnetic Observatory is of copper, 'No. 14,' silvered, and of which 

 1 meter weighs 2.6 grams. This arrangement promises to offer oppor- 

 tunities for a number of interesting experiments. We regard, not 

 without admiration, how a single pair of plates, brought into con- 

 tact at the farther end, instantaneously communicate a movement 

 to the magnetic bar, which is deflected at once for over a thousand 

 divisions of the scale." 



Further on in the same paper: 



"The ease with which the manipulator has the magnetic needle 

 in his command, by means of the communicator, had a year ago 

 suggested experiments of an application to telegraphic signaling, 

 which, with whole words and even short sentences, completely suc- 

 ceeded. There is no doubt that it would be possible to arrange an 

 uninterrupted telegraph communication in the same way between 

 two places at a considerable number of miles distance from each 

 other." 



The method of producing the currents in Gauss and Weber's experi- 

 ments was an application of the important discoveries of Faraday and 

 Henry, above referred to, in the induction of current by currents and 

 by magnets. 



On the recommendation of Gauss, this telegraph was taken up by 

 Steinheil, who, following their example, also used induced currents. 

 The important contributions of Steinheil were the discovery of the 

 earth return circuit, the invention of a telegraphic alphabet, and a 

 recording telegraph. Steinheil contributes an account of his telegraph 

 to Sturgeon's Annals of Electricity, in which the relative merits of 

 scopic, recording, and acoustic telegraphs are discussed, and the 

 advantages, which experience has since brought into prominence, of 

 the acoustic form are pointed out. 



Schiller's telegraph was exhibited at a meeting of German natural- 

 ists held at Bonn in 1835, and was there seen by Professor Muncke, of 

 Heidelberg, who, after his return to Heidelberg, made models of the 

 telegraph and exhibited them in his class room. These models were 

 seen by Cooke in the early part of 1836, and gave him the idea of intro- 

 ducing the electric telegraph in England. Cooke afterwards became 

 associated with Wheatstone, and a large number of ingenious arrange- 

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