AN IMPROVED COMPO- SITION FOR COATING THE BOTTOMS OF IRON SHIPS TO PREVENT THEIR FOULING, AND WHICH COMPOSITION MAY BE USED. AS A PROTECTIVE COATING FOR WOOD, IRON, OR OTHER SUBSTANCES, EXPOSED TO THE ACTION OF SEA WATER."
Year: 1862

page_text: LETTERS PATENT to Robert Johnson, of Liverpool, in the County of
Lancaster, Master Mariner, for the Invention of "AN IMPROVED COMPO-
SITION FOR COATING THE BOTTOMS OF IRON SHIPS TO PREVENT THEIR FOULING,
AND WHICH COMPOSITION MAY BE USED. AS A PROTECTIVE COATING FOR WOOD,
IRON, OR OTHER SUBSTANCES, EXPOSED TO THE ACTION OF SEA WATER."
PROVISIONAL SPECIFICATION left by the said Robert Johnson at the
Office of the Commissioners of Patents, with his. Petition,, on the 10th
January 1862.
I, ROBERT JOHNSON, of Liverpool, in the County of Lancaster, Master:
Mariner, do hereby declare the nature of the said Invention for "AN IMPROVED
COMPOSITION FOR COATING THE BOTTOMS OF IRON SHIPS TO PREVENT THEIR FOULING,.
AND WHICH COMPOSITION MAY BE USED AS A PROTECTIVE COATING FOR WOOD, IRON,.
OR OTHER SUBSTANCES EXPOSED TO THE ACTION OF SEA WATER," to be as follows
(that is to say):-
The object of this Invention is to prevent the fouling of the bottoms of iron
ships (and the wood, iron, and other substances used. in the construction of.
marine works) by the adhesion of animal or vegetable matter thereto, and
consists of a composition to be applied to the surface to be protected by
brushes, in a similar way to that now adopted in using oil paint.
This improved composition consists of mercurial or blue ointment (a mixture
of mercury and fatty matter), arsenic, and blacklead, in combination with
drying oil, oil paint, or common coal tar, or black varnish. It is preferred to
use the ingredients in about the following proportions:-Say, two pounds by

page_text: weight of the mercurial ointment, two pounds by weight powdered arsenic,
with six pounds by weight of blacklead in powder, to one gallon of coal tar
or black varnish; or paint oil, or oil paint, or other suitable vehicle; coal
tar or black varnish being preferred. It is preferred to apply this composition
over a coating of common coal tar or black varnish.
SPECIFICATION in pursuance of the conditions of the Letters Patent, filed
by the said Robert Johnson in the Great Seal Patent Office on the
10th July 1862.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, ROBERT
JOHNSON, of Liverpool, in the County of Lancaster, Master Mariner, send
greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her Letters
Patent, bearing date the Tenth day of January, in the year of our Lord
One thousand eight hundred and sixty-two, in the twenty-fifth year of Her
reign, did, for Herself, Her heirs and successors, give and grant unto me, the
said Robert Johnson, Her special licence that I, the said Róbert Johnson, my
executors, administrators, and assigns, or such others as I, the said Robert
Johnson, my executors, 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, exer-
cise, and vend, within the United Kingdom of Great Britain and Ireland,
the Channel Islands, and Isle of Man, an Invention for "AN IMPROVED COM-
POSITION FOR COATING THE BOTTOMS OF IRON SHIPS TO PREVENT THEIR FOULING,
AND WHICH COMPOSITION MAY BE USED AS A PROTECTING COATING FOR WOOD, IRON,
OR OTHER SUBSTANCES EXPOSED TO THE ACTION OF SEA WATER," upon the condition
(amongst others) that I, the said Robert Johnson, my executors or administra-
tors, by an instrument 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 Robert Johnson, do hereby declare the
nature of my said Invention, and in what manner the same is to be per-
formed, to be particularly described and ascertained in and by the following
statement (that is to say) :-
The object of this my said Invention is to prevent the fouling of the bottoms
of iron ships, and the wood, iron, and other substances used in the construction

page_text: of marine works by the adhesion of animal or vegetable matter thereto, and
consists of a composition to be applied to the surface to be protected, by
brushes, in a similar way to that now adopted in applying oil paint.
This my improved composition consists of mercurial or blue ointment (a
mixture of mercury and fatty matter), arsenick and blacklead, in combination
with drying oil, oil paint, or common coal tar, or black varnish. I prefer to
use the ingredients in about the following proportions:-Say, two pounds by
weight of the mercurial ointment, say, two pounds by weight powdered
arsenick, with, say, six pounds by weight of blacklead in powder, to one
gallon of coal tar, or black varnish; or paint oil, or oil paint, or other suitable
vehicle; coal tar or black varnish being preferred. I thoroughly amalgamate
the several ingredients by the use of a mill, or a pestle and mortar, or in any
other convenient way. I prefer to apply this composition over a coating of
common coal tar or black varnish.
Having now fully described and ascertained the nature of this my said
Invention, and how I believe the same may be best carried into practical
effect, I wish it to be understood that I do not confine myself to the precise
details or to relative proportions of the several ingredients used to make my
improved composition for protecting the bottoms of iron ships and other
surfaces exposed to the action of sea water from the adhesion thereto of
animal or vegetable substances, as it will be readily seen that the same may be
considerably varied without departing from the Invention; but what I do
claim as new and my Invention is, the composition herein-before described
and set forth, or any mere modification of the same, as a protective coating for
the bottoms of navigable vessels and other surfaces exposed to the action
of sea water, to prevent their fouling by the adhesion of animal or vegetable
matter thereto.
In witness whereof, I, the said Robert Johnson, have hereunto set my
hand and affixed my seal, this Ninth day of July, in the year of
our Lord One thousand eight hundred and sixty-two.
Witness,
WILLIAM WALKER,
Of 44, Castle Street,
Liverpool.
ROBERT (L.S.) JOHNSON.