A System of Submarine Signalling.
Year: 1894

page_text: Date of Application, 7th Aug., 1894-Accepted, 8th Sept., 1894
COMPLETE SPECIFICATION.
A System of Submarine Signalling.
I, LUCIEN J. BLAKE, of Lawrence, County of Douglas, State of Kansas,
United States of America, Professor of Physics and Engineering in the University
of Kansas, do hereby declare the nature of this invention and in what manner
the same is to be performed, to be particularly described and ascertained in and
by the following statement :-
The invention which forms the subject of my present application is a method or
system of electric communication more particularly designed for transmitting
intelligence between the shore and a lightship or other vessel which is permanently.
anchored beyond speaking distance from the land.
The practical difficulties in maintaining telegraphic or telephonic communication
between such ships and the shore by the use of submarine cables laid from the
shore and brought up from the bottom to the ship have been found too serious to
permit of their adoption. However well protected the cable may be, the constant.
motion of the ship produced by wind and tide, and the consequent twisting, chafing
and straining of the cables and their liability to foul with the anchor chain destroy
or render them useless in a very short time.
My purpose is to dispense with the suspended portion of the insulated or
protected cable, or that extending from the bottom up to the ship, and which is
the only part of the cable that is especially liable to injury, and one of the ways
in which I have accomplished this and still succeeded in maintaining perfect
telephonic communication with the ship is by utilizing the anchor and chain as
a part of the metallic circuit.
I have carried out my invention in the following manner: An insulated cable
was laid from the shore to a point near a lightship where its core was electrically
connected with the anchor of the ship. The anchor chain was in metallic
connection with the sheathing of the vessel at the hawse pipe through which it
passed. Between the sheathing of the ship and a submerged plate held at a short
distance from the ship's side a metallic circuit was established through a wire
to which was connected a telephonic transmitter and a receiver of very low,
resistance.
Similar instruments were connected with the shore end of the insulated cable,
and batteries provided for the transmitters.
With this arrangement perfectly clear speech was transmitted both from the
shore and from the ship through a very considerable length of intermediate
cable.
This plan, as described, may be modified in various ways without material
change in the result. For example, a transformer which converts from high to
low potential may be introduced between the cable and the anchor, the low
resistance coil of the transformer having one pole to ground and the other to the
anchor, while the high resistance coil may have its ends connected with the
conductors of a double cored cable, respectively, or one end to ground and
the other to the cable core. Also, the anchor chain may be insulated from the
ship's sheathing, and in that case the sheathing of the vessel may serve as
the submerged plate.
The accompanying drawing will serve as an illustration of the manner in which
the invention is or may be carried into effect.
Fig. 1 is a view showing the general relations of the ship, the shore and the
signalling apparatus.
Fig. 2 is a diagram illustrating the manner of using a transformer
:

page_text: A designates any permanently anchored vessel such as a lightship. B is the
chain and C the anchor.
D is an insulated cable running from the shore E and having its core electrically
connected with the anchor, or with the chain close to it.
At the shore station, and on board the ship are telephonic receivers F, F¹,
transmitters G G' and transmitting batteries H, H'. The above named instruments
at the shore end are connected with the cable circuit in the usual manner, while
those on the ship are in a circuit from the ship's sheathing or the anchor chain to a
submerged plate K, which is let down over the ship's side or suspended in the
water in any convenient way; or the ship's circuit may be from the anchor-chain
to the sheathing, if these are properly insulated from each other.
In lieu of connecting the cable directly to the anchor, the transformer, shown
in Figure 2, may be introduced between them. This transformer has a high
resistance coil, L, of which one terminal is connected with the insulated core of
the cable while the other ends in plate M lying on the bottom. The low
resistance coil N has one terminal connected with a plate ( lying on the bottom
and the other connected with the anchor.
In practice I have found it desirable to employ on the ship a telephone of
exceedingly low electrical resistance, and it is desirable to maintain between the
links of the chain as good electrical contact as possible. For this purpose it is
preferable to employ chains of non-corroding metal, such being now obtainable in
the market.
The principle of the invention is equally applicable when the ship is anchored
by means of a steel hawser instead of a chain, as is sometimes the case.
I have described the system as applied to a permanently anchored lightship,
but it is obvious that it may be applied to other analogous purposes, as for
instance for maintaining communication between the shore and an isolated
lighthouse built upon either a natural or an artificial foundation and to which
a cable connection is rendered difficult by exposure to the action of the waves,
drift ice or the like. In such case an insulated cable carried from the shore to
the lighthouse would be liable to chafe and wear out against the rocks. By my
present invention, a heavy conducting chain would be carried from the lighthouse
down to the bottom of the adjacent water, where it might be anchored in any
suitable way the end of the cable from shore would connect with such chain in
the manner already described in connection with lightships.
I am aware that the transmission of signals whether telegraphic or telephonic
over partially insulated or incomplete metallic circuits has been very frequently
practiced, and I do not claim this broadly. My present claim, however, is based
upon the discovery of a special way of successfully accomplishing a result
universally regarded as of great importance, but as to which all previous attempts
have been complete failures. The invention resides in the particular combination
of devices hereinbefore described.
Having now particularly described and ascertained the nature of my said inven-
tion and in what manner the same is to be performed, I declare that what I
claim is:
1. A system of signalling between an anchored lightship and the shore,
comprising in combination telephonic or telegraphic signalling instruments and
batteries on the ship and shore respectively, an insulated cable extending from the
shore station to the ship's anchor with which the core of the cable is electrically
connected, a conducting anchor chain or hawser, and a circuit on the ship from
said chain to a submerged metallic plate, said circuit including the signalling
instruments on the ship as set forth.
2. In a system of signalling between an anchored lightship and a shore station,
the combination with telephonic signalling instruments at the shore station, and
telephonic signalling instruments on the ship, of an insulated cable extending from
the instruments on shore to a point near the anchor, a conducting anchor chain or

page_text: hawser, a transformer interposed between the cable and the chain and having its
low resistance coil in circuit with the anchor chain and its high resistance coil in
circuit with the cable, and a circuit leading from the anchor chain to a submerged
plate over the ship's side and including the instruments on the ship.
Dated this 7th day of August 1894.
HASELTINE, LAKE & Co.,
45, Southampton Buildings, London, W.C., Agents for the Applicant.