IM- PROVEMENTS IN APPARATUS FOR PAYING-OUT SUBMARINE TELEGRAPH CABLES
Year: 1857

page_text: LETTERS PATENT to James Murdoch Napier, of Vine Street, York
Road, in the County of Surrey, Engineer, for the Invention of "IM-
PROVEMENTS IN APPARATUS FOR PAYING-OUT SUBMARINE TELEGRAPH CABLES."
Sealed the 16th February 1858, and dated the 19th August 1857.
PROVISIONAL SPECIFICATION left by the said James Murdoch Napier
at the Office of the Commissioners of Patents, with his Petition, on
the 19th August 1857.
I JAMES MURDOCH NAPIER, of Vine Street, York Road, in the County of
Surrey, Engineer, do hereby declare the nature of the Invention for "IMPROVE-
MENTS IN APPARATUS FOR PAYING-OUT SUBMARINE TELEGRAPH CABLES," to be as
follows:-
:
The Invention consists in means of applying, sustaining, and guiding cables
to aid in the paying-out of telegraph cables. For these purposes I provide
an endless cable with holders at fixed distances; these holders grip the tele-
graph cable near the ship, and relinquish their hold at the depth which may
be deemed sufficient. The endless cable thus sustains the weight of the tele-
graph cable as far down as may be required, and relieves it of strain down to
the point where the endless cable lets go its hold. The depth to which the
endless sustaining cable passes may be varied at pleasure, and when desired I
TISH

page_text: attach a weight to the lower end, to aid in sinking the telegraph cable; or
in place of an endless cable a cable is used with a weight attached to th
lower end, and the other end made fast on board the ship. The telegrap
cable is so attached to and conducted down this cable to the weight tha
during the process of paying-out from the ship the weight will influence the
direction of the depositing of the telegraph cable, and tend to make it fal
directly to the bottom of the water. In some cases a sustaining cable is used
one end of which is fixed on board ship, and a friction apparatus is attached
to the other or lower end, which is immersed in the water. The telegraph
cable passes through this friction apparatus, which takes a portion of the strain
off that part of the telegraph cable which is above the friction apparatus. I
also use a dip weight to depress this apparatus, and direct the fall of the
telegraph cable; and I can apply to the sustaining cable apparatus attached
at the lower immersed end, and so arranged that the paying-out of the telegraph
cable will give motion to a screw ejecting pump, or other propelling apparatus
forming part of the apparatus, which is thus moved forward under water in
the direction of the ship's course, thus assisting to lay the telegraph cable in a
direct line. I also use a dip weight with this apparatus, but in some cases
increase the weight of the apparatus instead. In constructing sustaining
cables where their upper ends are fixed, it is preferred to make them strongest
at their upper ends, and of decreasing strength as they are required to bear
less and less strain. In order to prevent the loss of the cable I secure that
the breaking point of the cable shall be on board the ship by passing it over
a small pulley; the instant the strain is taken off this pulley by the breaking
of the cable a mechanical action takes place, which stimulates a powerful
gripping apparatus placed in advance of the small pulley, and which is fixed
to a buoy; as soon as the retiring cable is seized it tears away the buoy from
the ship. The buoy is made of sufficient size to float and sustain the end of
the cable. The break apparatus used for controlling the running-out of the
telegraph cable is acted on and regulated by the flow of water or other
fluid through a passage capable of being regulated in its dimensions, by which
greater regularity may be obtained.