IMPROVE- MENTS IN ELECTRIC TELEGRAPHS
Year: 1857

page_text: PROVISIONAL SPECIFICATION left by Stanislas Hoga at the Office of
the Commissioners of Patents, with his Petition, on the 3rd November
1857,
I, STANISLAS HOGA, of Charlotte Street, Fitzroy Square, in the County of
Middlesex, do hereby declare. the nature of the said Invention for "IMPROVE-
MENTS IN ELECTRIC TELEGRAPHS," to be as follows:-
In communicating intelligence by means of the electric telegraph, I propose
by a certain arrangement of the galvanic batteries, and of the metallic plates
in the ground connected therewith, to enable two communicants to convey
intelligence to two recipients at the same moment without any danger of the
messages or telegrams being intermingled, and this I propose to effect where a
single wire only is used; where two wires are used four messages may by my
improved arrangements be sent and received momentarily, and so on, so that
by each continuous wire the number of telegraphic communications will in a
given time be doubled. The following are the simple means of effecting my
double telegraphic communication:-Two batteries are arranged at each of
the two stations, and one continuous wire connected with the four batteries
by being at each station in contact with two equal poles of the two batteries,
namely, at one station with the two positive poles, and at the other with the
two negative poles. The other two poles of the batteries at each station are
connected with two wires, each several hundred feet long, which being drawn

page_text: out in opposite directions terminate with two large metallic plates placed in
the ground. It is essential that the four plates in the ground connected with
the four batteries and wires be so situated as to form a parallelogram on the
globe, which may be effected without difficulty by previously ascertaining the
latitude and longitude of the two distant places, the stations. The two persons
at one station receiving a signal that two different messages will be sent to
them, detach their two batteries from all connection with the telegraph, bring-
ing in contact only the wires of the two plates in the ground with the one
continuous wire and the other telegraph instrument; by this arrangement,
when the two persons at the transmitting station both make contact of their
respective batteries, the two persons at the receiving station will both have a
signal of an action formed by a separate current of each battery; but if one
of the two persons at the transmitting station makes contact with his battery;
even in the very instant when the other breaks the contact of his battery, the
two persons at the receiving station will by that obtain two different signals,
namely, the person whose plate in the ground is in a straight line opposite to
the distant plate which is connected with the pole of the battery with which
the contact has been made will receive a signal of contact, whilst the other
person who receives communication by the plate which is in a straight line with
the plate connected with the battery with which the contact has been broken
will receive a signal of breaking contact, because the current, instead of tra-
versing a longer distance in the earth by a diagonal line of the parallelogram
formed by the four plates in the ground, will in preference take a shorter way
in a straight line from one plate to the other opposite plate, especially as each
plate presents sufficient surface for it to pass without obstruction, and it has
no need to deviate from its proper course incited by the attraction of the pole
of the battery. Thus the two different messages, in traversing the one con-
tinuous wire, do neither confuse the other, but remain distinct as if two
continuous wires had been used. It will be seen from the above that my
telegraph can be used in conjunction with any system, the action of which is
produced by making and breaking contact with the battery, but not by signals
made by reversing the current...