IMPROVEMENTS IN LIGHTNING CON DUCTORS
Year: 1868

page_text: LETTERS PATENT to Thomas Wood Gray, of 1, Margaret Street,
Limehouse, for the Invention of "IMPROVEMENTS IN LIGHTNING CON
DUCTORS."
Sealed the 19th January 1869, and dated the 20th July 1868.
PROVISIONAL SPECIFICATION left by the said Thomas Wood Gray
at the Office of the Commissioners of Patents, with his Petition, on
the 20th July 1868.
I, THOMAS WOOD GRAY, of 1, Margaret Street, Limehouse, do hereby
declare the nature of the said Invention for "IMPROVEMENTS IN LIGHTNING
CONDUCTORS," to be as follows:-
This Invention consists in the application of a system of lightning
conductors to ships or vessels of the composite build of wood and iron,
and also to those ships or vessels of iron with wood masts.
By preference I should fit both of above-mentioned class of vessels on
the system for which a Patent was granted to me 16th April 1867,
entitled "Improvements in Sir Wm. Snow Harris's Lightning Conductors
for Ships, Vessels, Buildings, and other Structures," namely, by fitting
plates and strips of metal from higher masts to lower masthead, &

page_text: from thence overboard, by means of tubular conductors down rigging,
as therein described.
In cases where the above-mentioned system may not be deemed
advisable the lower masts, topmasts, and higher masts are fitted, as is
well known, with plates or strips of metal, and connected to the hull
of vessel, in the case of a composite vessel, by fitting strips or plates
of metal by preference on wood or other non-conducting material,
or otherwise over iron beams of vessel, on under side of wood deck, and
thence to ship's side with through metal bolts to copper outside, and
the connections from heel of lower mast fitted in a similar manner,
but in any case so that the hull shall have an entirely distinct line of
conductors quite independent of any iron, and where possible removed
from all contact with the same.
In the case of iron vessels with wood masts, by plates or strips
of metal taken from the bottom of masts on deck, along upper side
of wood deck to ship's side, and from thence overboard, this system
being more especially adapted to vessels with tabernacle masts, or where
the masts step at the upper deck.
SPECIFICATION in pursuance of the conditions of the Letters Patent,
filed by the said Thomas Wood Gray in the Great Seal Patent
Office on the 19th January 1869.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, THOMAS
WOOD GRAY, of 1, Margaret Street, Limehouse, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her
Letters Patent, bearing date the 20th day of July, in the year of
our Lord One thousand eight hundred and sixty-eight, in the thirty-
second year of Her reign, did, for Herself, Her heirs and successors, give
and grant unto me, the said Thomas Wood Gray, Her special licence
that I, the said Thomas Wood Gray, my executors, administrators, and
assigns, or such others as I, the said Thomas Wood Gray, my exe-
cutors, administrators, and assigns, should at any time agree with, and no
others, from time to time and at all times thereafter during the term
therein expressed, should and lawfully might make, use, exercise, and
vend, within the United Kingdom of Great Britain and Ireland, the
Channel Islands, and Isle of Man, an Invention for "IMPROVEMENTS IN

page_text: LIGHTNING CONDUCTORS," upon the condition (amongst others) that I, the
said Thomas Wood Gray, my executors or administrators, by an instru-
ment in writing under my, or their, or one of their hands and seals,
should particularly describe and ascertain the nature of the said
Invention, and in what manner the same was to be performed, and
cause the same to be filed in the Great Seal Patent Office within six
calendar months next and immediately after the date of the said Letters
Patent.
NOW KNOW YE, that I, the said Thomas Wood Gray, do hereby
declare the nature of my said Invention, and in what manner the same
is to be performed, to be particularly described and ascertained in and
by the following statement :-
This Invention consists in the application of a system of lightning
conductors to ships or vessels of a composite build of wood and iron, and
also to ships or vessels of iron with wood masts.
In the case of a composite built vessel of wood and iron with wood
lower masts the iron beams or any iron whereon the line of conductors
are fixed is to be covered with wood or other non-conducting material,
and the plates of metal or strips of copper by preference used as
lightning conductors are fixed on the same or on the under side of wood
deck to ship's side, and partly down the ship's side with direct metal
bolts in connection thro' the ship's side to the metal outside, or to the
water, more particularly in the case of a double planked or skinned ship's
side, so that there may be independent metal bolts for connecting the
metal plates or strips with the metal or water outside. The connections
from the heel of masts to bottom of vessel are made in a similar manner,
the conductors being fitted over non-conducting materials, with separate
bolts through the bottom, so that there shall be a distinct line of metal
conductors quite independent and apart from any iron, and removed
from all direct contact with the same in the interior of the hull to avoid
the danger attending the magnetising of the iron to the detriment of the
action of the compasses, and with double skinned vessels to avoid
all danger of an explosive action, and in all cases to prevent any risk
of the electric fluid going to any superior conducting material, such as
the metal or copper lining of the magazine.
In the case of a composite vessel with tabernacle masts or masts step-
ping on or terminating at the deck the same to be fitted from heel of
mast along upper side of wood deck to ship's side, and thence overboard

page_text: to sea direct, the masts if of wood fitted as usual with plates or strips
of metal.
In the case of composite vessel with iron lower masts I would fit the
system patented by me 16th April 1867.
Having stated the nature of my Invention I would have it understood
that I do not claim the separate parts but the combination of the whole to
secure a line of conductors, copper by preference, fixed on non-conducting
material as described, and having no connection or contact with the
iron interior portion of the vessel, and that by preference I should fit all
vessels of whatever construction on the system patented by me 16th April
1867.
What I claim is, the fitting of conductors as described to composite
vessels of wood and iron in such manner that there shall be a direct line
of metal conductors of any form, quite independent and free from direct
contact with any iron in the interior of the vessel.
In witness whereof, I, the said Thomas Wood Gray, have hereunto
my hand and seal, this 18th day of January, in the year of our
Lord 1869.
THOMAS WOOD GRAY. (L.S.)