44 
developed to some extent by Gauss and Weber, who used it for experi- 
mental purposes. The following quotation referring to Gauss and Weber’s 
telegraph, from Poggendorf’s Annalen, is of considerable historical 
interest: : 
“There is, in cConnection 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 Mag- 
netic 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. 35,’ of which one meter weighs eight 
grammes. The wire of the multipliers in the magnetic observatory of cop- 
per ‘No. 14,’ silvered, of which one meter weighs 2.6 grammes. This 
arrangement promises to offer opportunities for a number of interesting 
experiments. We regard, not without admiration, how a single pair of 
plates, brought into contact at the further end, instantaneously communi- 
cates 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 com- 
mand, by means of the communicator, had a year ago suggested experi- 
ments of an application to telegraphic signaling, which, with whole words 
and even short sentences, Completely succeeded. There is no doubt that 
it would be possible to arrange an uninterrupted telegraph communica- 
tion 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 the 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, 
