368 



SGIENGE. 



[N. S. Vol. VII. No. 168. 



9,000 (Prussian) feet. The line wire is 

 mostly of copper, of that known as ' No. 

 3,' of which one metre weighs eight 

 grammes. The wire of the multipliers in 

 the Magnetic Observatory is of copper, ' No. 

 14,' silvered, and of which one metre 

 weighs 2.6 grammes. This arrangement 

 promises to offer opportunities for a num- 

 ber of interesting experiments. We re- 

 gard, not without admiration, how a single 

 pair of plates, brought into contact at the 

 farther end, instantaneously communicate 

 a movement to the magnetic bar, which is 

 deflected at once for over a thousand divis- 

 ions of the scale," Further on in the same 

 paper : " The ease with which the manipu- 

 lator has the magnetic needle in his com- 

 mand, by means of the communicator, had a 

 year ago suggested experiments of an appli- 

 cation to telegraphic signalling, which, with 

 whole words and even short sentences, com- 

 pletely succeeded. There is no doubt that it 

 would be possible to arrange an uninter- 

 rupted 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 experiments was an ap- 

 plication 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 re- 

 turn circuit, the invention of a telegraphic 

 alphabet and a recording telegraph. Stein- 

 heil contributes an account of his telegraph 

 to Sturgeon's Annals of Electricity in which 

 the relative merits of scopic, recording and 

 acoustic telegraph 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 naturalists held at 

 Bonn in 1835, and was there seen by Pro- 

 fessor 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 introducing the electric telegraph in 

 England. Cooke afterward became asso- 

 ciated with Wheatstone, and a large num- 

 ber of ingenious arrangements for telegraph- 

 ing was the result. Many of the later 

 developments by Wheatstone are still in 

 use and are hard to beat. 



Steinheil appears to have been antici- 

 pated in the idea of making the telegraph 

 self-recording by Morse, who, according to 

 evidence brought forward by himself, 

 thought out some arrangements as early as 

 1832. Exactly what Morse's first ideas 

 were seems somewhat doubtful, and he did 

 nothing till 1835, when he made a rough 

 model of an electro-magnetic recording tele- 

 graph. Morse's mechanical arrangements 

 were of little merit, and his alphabet and 

 method of interpretation by a dictionary 

 were clumsy and inconvenient. The chief 

 point of interest in connection with the 

 early history of the Morse telegraph was 

 the proposal to make use of Sturgeon's dis- 

 covery of electro- magnetism of soft iron. 

 Morse, however, seems to have known prac- 

 tically nothing of the subject except that 

 iron could be magnetized by a current, and 

 in consulting his colleague. Dr. Gale, he was 

 unwittingly led to use the discoveries of 

 Henry, who had previously practically 

 solved the whole problem. MucJi of the 

 subsequent improvement in the mechan- 

 ical arrangements were due to Vail, who 

 became associated with Morse, and the 

 Morse code as we now know it was almost, 

 if not entirely, worked out by Vail. Con- 

 siderable dispute and some litigation arose 

 over Morse's claims, but that is outside our 



