A NEW MEANS OF ELECTRICAL COMMUNICATION BETWEEN VESSELS AT SEA AND THE SHORE, OR BETWEEN-TWO OR MORE VESSELS AT.SEA
Year: 1879

page_text: PROVISIONAL SPECIFICATION left by Severin Lauritzen, Walter Claude
Johnson, and Samuel Edmund Phillips at the Office of the Commissioners of
Patents on the 2nd August 1879.
tr
SEVERIN LAURITZEN, Telegraph Engineer, of Copenhagen, Denmark, and WALTER
CLAUDE JOHNSON and SAMUEL EDMUND PHILLIPS, both of Victoria Works, Victoria
Road, Charlton, in the County of Kent, Engineers and Electricians. A NEW
MEANS OF ELECTRICAL COMMUNICATION BETWEEN VESSELS AT SEA AND THE SHORE,
OR BETWEEN-TWO OR MORE VESSELS AT.SEA."
This Invention relates to a method by which a ship can communicate with the
shore, or the shore with a ship, and its chief applications would be as follows:-
First. Ships nearing the coast could report themselves to the shore and receive
instructions from the shore.
Second. Light ships or vessels permanently stationed off the coast for telegraphic
or other purposes can communicate with the shore, and vice versa.
Third. Ships could be guided into safe channels during foggy weather and made
aware of their approach to rocks or shallow water.
Fourth. In the repair of telegraphic cable when two or more cables are laid closo
together, one can be distinguished from the other, or the exact position of a cable
may be ascertained before lowering the grapnel, and in the case of a broken cable,
the ship can be made aware which side of the break she is, or a bad leakage may
be localized.
We will now describe the nature of our Invention in relation to its first.
application, the following applications will then be self-evident and will not require
detailed explanation.
To enable a ship and the shore to communicate with each other, a telegraphic
cable is laid out to sea for the required distance, and the passing vessel is provided
with a short length of cable which is trailed along the bottom of the sea; this cable
we will speak of as the trailing cable, and the cable from the shore we will call the
permanent cable.
For the ship to communicate with the shore currents of electricity are sent
into the trailing cable, and when this approaches or passes over the permanent
cable, these currents will be appreciable on shore by means of a telephone, galvano-
meter, or any other suitable method of appreciating electric currents, but pre-
ferably by the former.

page_text: For the shore to communicate with the ship, the shore sends currents into the
permanent cable; when the trailing cable from the ship passes over or approaches
the permanent cable these currents will be appreciable on board.
The cable from the shore having been laid out from the sea to the required
distance might, with advantage be laid backwards and forwards over a certain area
so that passing vessels would the more easily pass over it with their trailing cables,
or in the case of a vessel permanently stationed off the coast, such as a light' ship,
the permanent cable might here also be laid backwards and forwards for a certain
distance, so as to cover the area over which the light ship would swing; the vessel
would then simply have to drop the end of a small cable overboard so that a short
length would lay on the bottom, wlien she would be in a position to send or receive
signals from the shore.
.
To guide ships into safe channels or warn them of their approach to rocks or
shallow water, a permanent cable should be laid from the shore and currents of
electricity having a definite character given to them sent into the cable; when the
vessel with its trailing cable approaches or passes this permanent cable the warning
signals would be received on board, and by a prearrangement the ship would then
know which way to steer or what to do.
When two or more ordinary telegraphic cables are laid near each other, and it is
desired to distinguish one from the other for the purpose of repair or otherwise, the
vessel would pay out the trailing cable, when any prearranged currents sent into
the submerged cables would be appreciable on board, and the vessel could tell which
cable she was near.
Or with a cable that had been parted, one kind of signals could be sent into one
end from one shore, and another kind of signals into the other end from the other
shore, and in this way the ship with her trailing cable could tell which end she was
over, or in other words, which side of the brake she was, or in a cable with a bad
leakage if strong currents were sent into the cable from the shore, the ship by
dragging her trailing cable along the submerged cable would be able to tell when
-she was over-the-leakage.--