IMPROVE- MENTS IN ELECTRIC AND MAGNETIC TELEGRAPHS
Year: 1859

page_text: PROVISIONAL SPECIFICATION left by Andrew Barclay at the Office
of the Commissioners of Patents, with his Petition, on the 7th January
1859.
I, ANDREW BARCLAY, of Kilmarnock, in the County of Ayr, North Britain,
Engineer, do hereby declare the nature of the said Invention for "IMPROVE-
MENTS IN ELECTRIC AND MAGNETIC TELEGRAPHS," to be as follows:-
This Invention relates to some extent to two Inventions of improvements
in electric, magnetic, and electro-magnetic telegraph ropes or conductors;
also improvements in obtaining and distributing or applying electricity and
magnetism, and in obtaining motive power therefrom, for which I have
obtained provisional protection, and it consists of certain arrangements whereby
electric and magnetic telegraphs may be rendered of superior efficiency in
working.
The electric or magnetic cable, rope, or conductor is connected to an iron
ship, or to the metallic surfaces of any ship or other vessel, or collection of
metallic surfaces in the sea or in any fluid matter, such connection being made
by means of a series of collecting or transmitting wires on the general
principle already explained in the Provisional Specification of "improvements
in obtaining and distributing or applying electricity and magnetism, and in
obtaining motive power therefrom for the purpose of securing a reservoir or
receiver, and distributor and conductor of the actuating power. In working
according to these improvements, apparatus on the galvanometrical principle
is used for the signalling process.

page_text: The galvanometer is constructed with several wires, and the whole apparatus
is so arranged, that the sender of a message uses but one or a portion of such
wires for the transmission of his signals, whilst the return current passes
through a portion or the whole of the wires, and the sender passes merely so
much electricity through the galvanometer as suffices for the work to be done,
whilst the rest passes on.
The external wires of the cable are also used for the transmission of
electrical currents, and hence two separate lines of electricity may be worked
in one single cable, one passing through the internal wire or wires, and the
other through the sheath or covering wires. Instead of constructing the
galvanometer with a number of wires, one wire only may be used, the elec-
tricity being divided off by several conducting wires so as to secure the result
herein-before referred to. To regulate the quantity of electricity, a cup'or cell
containing a weak conducting solution may be used, such cup being disposed
in the line of the conducting wire. The conducting power may thus be
regulated by varying the strength or quality of the liquid used. Instead of
'this plan, a wire of weaker conducting power may be inserted in the line.
Another portion of the improvements relates to the use of a wire, or wires
or cables for telegraphing purposes totally uninsulated, that is to say, with such
wires merely protected mechanically or entirely uncovered, the object being
to operate with telegraph wires, without in any way resorting to what is
technically known as electrical or magnetic insulation.