After this in some sort prehistoric period had been rapidly run through, he would have to follow very closely the development of electric telegraphy.

Almost from the outset, and shortly after Ampere had made public the idea of constructing a telegraph, and the day after Gauss and Weber set up between their houses in Goettingen the first line really used, it was thought that the conducting properties of the earth and water might be made of service.
The history of these trials is very long, and is closely mixed up with the history of ordinary telegraphy; long chapters for some time past have been devoted to it in telegraphic treatises.

It was in 1838, however, that Professor C.A.Steinheil of Munich expressed, for the first time, the clear idea of suppressing the return wire and replacing it by a connection of the line wire to the earth.

He thus at one step covered half the way, the easiest, it is true, which was to lead to the final goal, since he saved the use of one-half of the line of wire.

Steinheil, advised, perhaps, by Gauss, had, moreover, a very exact conception of the part taken by the earth considered as a conducting body.