IMPROVEMENTS CONNECTED WITH SUBMARINE CABLE GRAPNELS FOR ASCERTAINING WHEN THE GRAPNEL IS ON THE SEA BOTTOM
Year: 1885

page_text: "
We Sir JAMES ANDERSON, Knight, Managing Director and ARTHUR EDWIN
KENNELLY, Electrician, both of No 66 Old Broad Street in the City of London,
do hereby declare the nature of our invention for IMPROVEMENTS CONNECTED
WITH SUBMARINE CABLE GRAPNELS FOR ASCERTAINING WHEN THE GRAPNEL IS ON
THE SEA BOTTOM to be as follows:-
"
This invention has for its object to afford indications on board ship when a
grapnel is in contact with the sea bottom while dragging for electric cables during
repairing operations.
For this purpose we combine with the grappling rope an insulated electrical
conductor which at or near the grapnel is connected to means or apparatus
whereby an electrical current is conveyed through the conductor to an indicator on
board ship so long as the grapnel is in contact with the sea bottom, but which
current ceases so soon as the grapnel leaves the bottom. Or on the other hand
whereby a current is conveyed through the conductor so long, as the grapnel
remains suspended but which current ceases so soon as the grapnel touches the
bottom.
The means or apparatus whereby a current is conveyed through the conductor
under the above conditions may be variously contrived and arranged. According
to one arrangement the end of the conductor is made to enter a closed vessel, from
which it remains insulated so long as the rope or grapnel to which it is attached
shall remain vertical, but from which it ceases to be insulated so soon as the rope
or grapnel shall depart from verticality or from such a degree of approximation to
verticality as shall be in every case adjusted and decided. Such cessation of
insulation may be effected by various means such as by a liquid or liquids in the
vessel, which when the vessel assumes a more or less inclined position, establishes
a contact between the insulated conductor and the vessel and through this with
the earth, thereby closing an electrical circuit whereby an indicator on board ship
is actuated. The said vessel may be conveniently constructed of spherical shape
made in two halves tightly closed. To the one half is connected a tube through
which the insulated conductor from the grapnel rope enters, the conductor being
connected to a cup shaped piece of metal, also insulated from the casing. The

page_text: other part of the globe has an opening through which a suitable quantity of
mercury is introduced, after which the globe is filled with paraffin oil or other
non-conducting fluid, and the opening is then closed hermetically by a screw-plug.
Thus when the globe is suspended from the rope in a vertical. position owing to
the grapnel being removed from the sea bottom, the mercury will lie in the bottom
of the globe, and the said cup will remain insulated. So soon however as the
grapnel or that part of the rope in which the apparatus is fixed touches the
bottom, the globe will assume a more or less horizontal position so that the
mercury will come in contact with the cup and will thus establish electrical
communication between the conductor and the globe casing, and through this with
the earth. By this means it will be seen that whenever the grapnel leaves the sea
bottom, or even when it is dangerously near doing so, an indication of the fact will
be given on board ship, shewing that more rope is required to be payed out.
By filling the globe with a non-conducting liquid, the several purposes are served
of keeping the mercury steady and preventing it from making false contacts owing
to jerks of the rope; of keeping the inner surfaces of the vessel clean and free
from tendency to oxidate; and of aiding the vessel in resisting the pressure of the
sea at great depths.
The above described apparatus may be advantageously combined with that
described in the Specification to Letters Patent granted to Anderson and Johnson
dated 17th May 1882 N° 2311, wherein an electric conductor combined with the
grapnel rope was connected to appliances in the grapnel, whereby the presence of
the electrical cable in the grapnel was indicated on board ship, and whereby also
electrical communication could be established between the cable and the ship. In
combining the present invention with this apparatus a branch is led from the
conductor to the before described vessel and this branch conductor may in this case
be connected to the before mentioned metal cup through a resistance coil. Thus
supposing that the grapnel shall put the insulated conductor of the rope to earth
on the hooking of the cable, as described in the said Specification, the present
apparatus will, before the grapnel has hooked the cable, put the conductor to earth
through the resistance coil, but as soon as the cable is hooked, the grapnel will
short circuit the said resistance, and thus an indication of the fact will be given
through the conductor on board ship.
Although we have described an arrangement wherein the electrical current is
passed through the conductor by causing a contact to be made when the grapnel is
on the sea bottom, yet it will be evident that any other convenient device for
establishing or disestablishing a current, not necessarily involving the making and
breaking of a contact, may be employed for the purpose of this invention.
100

page_text: COMPLETE SPECIFICATION.
We Sir JAMES ANDERSON, Knight, Managing Director, and ARTHUR EDWIN
KENNELLY, Electrician, both of No 66 Old Broad Street in the City of London,
do hereby declare the nature of our invention for "IMPROVEMENTS CONNECTED
WITH SUBMARINE CABLE GRAPNELS FOR ASCERTAINING WHEN THE GRAPNEL IS
ON THE SEA BOTTOM," and in what manner the same is to be performed to be
particularly described and ascertained in and by the following statement :—
This invention has for its object to afford indications on board ship when a
grapnel is in contact with the sea bottom while dragging for electric cables during
repairing operations.
For this purpose we combine with the grappling rope an insulated electrical
conductor which at or near the grapnel is connected to means or apparatus whereby
an electrical current is conveyed through the conductor to an indicator on board
ship so long as the grapnel is in contact with the sea bottom, but which current
ceases or is varied so soon as the grapnel leaves the bottom. Or on the other hand
whereby a current is conveyed through the conductor so long as the grapnel
remains suspended but which current ceases or is varied so soon as the grapnel
touches the bottom.
The means or apparatus whereby a current is conveyed through the conductor
under the above conditions may be variously contrived and arranged.
According to one arrangement the end of the conductor is made to enter a closed
vessel, from which it remains insulated so long as the rope or grapnel to which it
is attached shall remain vertical, but from which it ceases to be insulated so soon
as the rope or grapnel shall depart from verticality or from such a degree of
approximation to verticality as shall be in every case adjusted and decided. Such
cessation of insulation may be effected by various means, such as by a liquid or
liquids in the vessel, which when the vessel assumes a more or less inclined
position establishes a contact between the insulated conductor and the vessel and
through this with the earth, thereby closing an electrical circuit whereby an
indicator on board ship is actuated. The said vessel may be conveniently con-
structed of spherical shape made in two halves. tightly closed. To the one half is'
connected a tube through which the insulated conductor from the grapnel rope
enters, the conductor being connected to a cup shaped piece of metal, also insulated
from the casing. The other part of the globe has an opening through which
a suitable quantity of mercury is introduced, after which the globe is filled with
paraffin oil or other non-conducting fluid, and the opening is then closed her-
metically by a screw plug. Thus when the globe is suspended from the rope in
a vertical position owing to the grapnel being removed from the sea bottom, the
mercury will lie in the bottom of the globe and the said cup will remain insulated.
So soon however as the grapnel or that part of the rope in which the apparatus is
fixed touches the bottom, the globe will assume a more or less horizontal position
so that the mercury will come in contact with the cup and will thus establish
electrical communication between the conductor. and the globe casing, and through
1.
:

page_text: this with the earth. By this means it will be seen that' whenever the grapnel
leaves the sea bottom, or even when it is dangerously near doing so, an indication
of the fact will be given on board ship, shewing that more rope is required to be
payed out.
By filling the globe with a non-conducting liquid, the several purposes are served
of keeping the mercury steady and preventing it from making false contacts owing
to jerks of the rope; of keeping the inner surfaces of the vessel clean and free
from tendency to oxidate; and of aiding the vessel in resisting the pressure of the
sea at great depths.
The above described apparatus may be advantageously combined with that
described in the Specification to Letters Patent granted to Anderson and Johnson
dated 17th May 1882 N° 2311, wherein an electric conductor combined with the
grapnel rope was connected to appliances in the grapnel, whereby the presence of
the electrical cable in the grapnel was indicated on board ship, and whereby also
electrical communication could be established between the cable and the ship.
In combining the present invention with this apparatus a branch is led from the
conductor to the before described vessel and this branch conductor may in this
case be connected to the before mentioned metal cup through a resistance coil.
Thus supposing that the grapnel shall put the insulated conductor of the rope to
earth on the hooking of the cable, as described in the said Specification, the present
apparatus will, before the grapnel has hooked the cable, put the conductor to earth
through the resistance coil, but as soon as the cable is hooked, the grapnel will
short-circuit the said resistance, and thus an indication of the fact will be given
through the conductor on board ship.
Although we have described an arrangement wherein the electrical current is
passed through the conductor by causing a contact to be made when the grapuel
is on the sea bottom, yet it will be evident that any other convenient device for
establishing or disestablishing a current, not necessarily involving the making and.
breaking of a contact, may be employed for the purpose of this invention.
Fig. 1 of the accompanying drawings shews a vertical section of one arrangement
of the before described apparatus for carrying out our invention. A is the closed
vessel, baving a stuffing box at B through which the insulated conductor C con-
nected with the grapnel rope passes in a water tight manner into the vessel, which
also has an opening at bottom hermetically closed by a screwed cap D, in which is
a small passage E closed by a screwed plug F.
On removing the cap D access is gained to the conductor, while the small
passage E serves for the introduction of the mercury G and the oil H, with which
the vessel is entirely filled. To the inner end of the conductor C is secured the
metal cup I, so that when by reason of the metal vessel A being in contact with the
bottom of the sea, it is made to assume an inclined position, the mercury G comes 4
in contact with the edge of the cup I, thus establishing electrical communication
between the conductor C and the metal vessel, which, being surrounded by sea water,
makes an efficient electrical earth connection, and causes a signal to be actuated
on board ship through the conductor.
When the vessel A assumes a vertical or nearly vertical position, in consequence
of its leaving the sea bottom, or being on the point of doing so, the contact between
the mercury and the cup will cease, and the consequent cessation of the current will
at once indicate the fact on board ship, thus giving notice that more rope is required.
to be payed out.
Fig. 2 shews a section of the same construction of apparatus modified for the 5
purpose of being employed in combination with Anderson and Johnsons invention.
herein before mentioned.
For this purpose the conductor O communicates with the cup I through a
resistance coil K which, together with the cup, is mounted on a sheath L of
insulating material, so that when the vessel A is on the sea bottom and the grapnel 5
has not yet hooked the cable, only a weak current will be passed through the
conductor, giving a weak indication on board ship, while when the cable has been

page_text: hooked and the conductor thereby put to earth, the grapnel will short circuit the
resistance, thus giving a stronger indication on board.
On the other hand, when the vessel leaves the bottom in dragging, the current
will be entirely intercepted as before described.
As before stated, our invention may be carried out in a great variety of
ways, and we in no way limit ourselves to the construction of apparatus herein
described.
Having now particularly described and ascertained the nature of our said
invention, and in what manner the same is to be performed, we declare that what,
we claim is
1. The combination with an insulated conductor in the rope of a submarine cable
grapnel, of means or apparatus so arranged that when in dragging for a cable the
grapnel leaves the sea bottom or is in danger of doing so, an electrical current
in the couductor is automatically intercepted, produced or varied so as to give
an indication.on board ship, substantially as and for the purposes herein described.
2. In combination with the rope of a submarine cable grapnel, an insulated
conductor having a metallic vessel connected to the free end thereof and so
arranged that while the vessel lies upon the sea bottom a contact is established
between the said vessel and the conductor, such contact being broken when the
vessel leaves the bottom or is about to do so, substantially as herein described.
3. The combination with apparatus such as is described in the Specification to
Anderson and Johnsons Patent N° 2311 of 1882, of a branch to the conductor in
the grapnel rope, connected to a metal vessel with which the conductor makes
contact through a resistance coil while the grapnel is on the sea bottom such
resistance being short circuited on the hooking of the cable by the grapnel,
substantially as and for the purposes herein described.
4. The construction of apparatus for indicating when a submarine cable grapnel
is on the sea bottom as herein described with reference to the accompanying
drawing.