IM- PROVED COMPOSITIONS FOR COATING THE BOTTOMS OF IRON, STEEL, AND WOODEN SHIPS AND OTHER NAVIGABLE VESSELS AND MARINE WORKS: GENERALLY
Year: 1867

page_text: LETTERS PATENT to Joseph de Silva, of Liverpool, in the County of.
Lancaster, Painter and Paint Manufacturer, for the Invention of "IM-
PROVED COMPOSITIONS FOR COATING THE BOTTOMS OF IRON, STEEL, AND
WOODEN SHIPS AND OTHER NAVIGABLE VESSELS AND MARINE WORKS:
GENERALLY."
Sealed the 24th April 1868, and dated the 28th October 1867.
PROVISIONAL SPECIFICATION left by the said Joseph de Silva at the
Office of the Commissioners of Patents, with his Petition, on the
28th October 1867.
I, JOSEPH DE SILVA, of Liverpool, in the County of Lancaster, Painter and
Paint Manufacturer, do hereby declare the nature of the said Invention for
"IMPROVED COMPOSITIONS FOR COATING THE BOTTOMS OF IRON, STEEL, AND WOODEN:
SHIPS AND OTHER NAVIGABLE VESSELS AND MARINE WORKS GENERALLY," to be as
follows (that is to say) :-
This Invention has for its object certain improved compositions for coating.
the bottoms of iron, steel, composite, and wooden ships to prevent the same
from fouling by the adhesion of animal and vegetable matter, or both, and in
case of wooden ships that are not sheathed with metal an under coating is first
applied to guard them against the attack of worms.
The coating for iron ships and upper coating for wooden ships consists of
the following ingredients, namely:-Bridgewater paint or fireproof paint, a
mineral found in America resembling oxide of iron, pure zinc, pure white

page_text: lead, strychnine ground in boiled oil to a stiff consistency, arsenic, and
"lobelia inflata." The foregoing ingredients are mixed in about equal pro-
portions, except the arsenic, which is in excess in proportion to the "lobelia
iuflata," and the mixture is thinned chiefly with bright varnish and tar oil,
and when required a little spirits of genuine turpentine.
The composition applied to the bottom of wooden ships to preserve them
against the attack of worms consists of verḍegris or eurigo and metallic green
paint, composed of metallic oxide of copper and arsenic, to which is added a
little pure zinc and dry white lead, to give a stiff consistency, ground in boiled
oil and copal varnish, to which it is preferred to add a little strychnine.
This under coating may be applied to the surfaces to be coated in either a
hot or cold state, but must be allowed to get perfectly dry before applying the
upper coating.
SPECIFICATION in pursuance of the conditions of the Letters Patent, filed
by the sail Joseph de Silva in the Great Seal Patent Office on the
28th April 1868.
TO ALL TO WHOM THESE PRÉSENTS SHALL COME, I, JOSEPH
DE SILVA, of Liverpool, in the County of Lancaster, Painter and Paint
Manufacturer, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her Letters
Patent, bearing date the Twenty-eighth day of October, in the year of our Lord
One thousand eight hundred and sixty-seven, in thirty-first year
did, for Herself, Her heirs and successors, give and grant unto me, the
said Joseph de Silva, Her special license that I, the said Joseph de Silva, my
executors, administrators, or assigns, or such others as I, the said Joséph
de Silva, 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
terin 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 "IMPROVED COMPOSITIONS FOR COATING
THE BOTTOMS OF IRON, STEEL, AND WOODEN SHIPS AND OTHER NAVIGABLE VESSELS
AND MARINE WORKS GENERALLY," poй the condition (amongst others) that I,
the said Joseph de Silva, my executors or administrators, by an instrument
in writing under my, or their, or one of their hands and seals, should parti-
cularly describe and ascertain the nature of the said Invention, and in what
planner the same was to be performed, and cause the same to be filed in

page_text: 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 Joseph de Silva, 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 state-
ment (that is to say) :-
This my said Invention has for its object the protection of the bottoms of
iron and steel ships and other navigable vessels, to prevent the oxidation and
fouling of the same by the adhesion of animal and vegetable matter or either;
also to prevent the fouling of the bottoms of wooden vessels by the adhesion
of animal and vegetable matter, and to guard the same against the attack of
worms, which I do by applying to the bottoms of iron and steel ships a
coating formed of the following ingredients, namely:-Bridgewater paint, a
fire-proof paint, a mineral found in America resembling oxide of iron, pure
zinc, pure white lead, and strychnine ground in boiled oil to a stiff con-
sistency, arsenic, and lobelia inflata. These ingredients are combined in about'
equal proportions, except the arsenic, which is in excess to the proportion to
the lobelia inflata. To the several materials is added chiefly bright varnish
and tar oil, and when required a little spirit of genuine turpentine. The
whole of these ingredients are thoroughly amalgamated, and are applied to the
bottoms of the vessels to be coated, either in a hot or cold state, by a brush in
the same way as ordinary paint.
In applying this composition to wooden or composite ships or other
navigable vessels which are not sheathed with metal, as an additional pro-
tection against the fouling and attack of worms, I prefer to apply an under
coating composed of the following ingredients:-Verdegris or eurigo and
metallic green paint, composed of metallic oxide of copper and arsenic, to
which is added a little pure zinc and dry white lead to give a stiff consistency.
The ingredients are ground in boiled oil and copal varnish, to which it is
preferred to add a little strychnine. This uuder coating can also, in the
case of the one for iron ships, be applied to the surfaces to be covered in either
a hot or cold state, after which the composition first described is applied as an
outer coating on the top thereof; but I have found by practical experience
that in some cases the outer coating may be dispensed with, as the com-
position not only protects the wood from the attack of worms, but it also to a
great extent prevents fouling by the adhesion of animal and vegetable matter
to wooden surfaces coated therewith.
Having now fully described and ascertained the nature of this my said
Invention, and the best mode I am acquainted with for carrying the same into

page_text: practical effect, I wish it to be understood that I do not confine myself to the
precise relative proportions of the several ingredients herein described and set:
forth, as it will be readily seen the relative proportions may be slightly. varied
without material injury to the composition; but what I claim as new, useful,
and my Invention is, the compositions herein-before described and set forth,
substantially in the manner and for the purposes berein-before stated.
In witness whereof, I, the said Joseph de Silva, have hereunto set my
hand and affixed my seal, this Twenty-seventh day of April, in the
year of our Lord One thousand eight hundred and sixty-eight.
Witness,
WILLIAN WALKER,
of 44, Castle Street,
Liverpool.
JOSEPH DE SILVA. (L.S.)