AN IMPROVED METALLIC PAINT FOR PRE- VENTING THE CORROSION AND FOULING OF SHIPS' BOTTOMS AND OTHER SURFACES IN WATER
Year: 1870

page_text: ETTERS PATENT to William Robert Lake, of the "International
Patent Office," Southampton Buildings, London, Consulting Engi-
neer, for the Invention of "AN IMPROVED METALLIC PAINT FOR PRE-
VENTING THE CORROSION AND FOULING OF SHIPS' BOTTOMS AND OTHER SURFACES
IN WATER." -A communication from abroad by James Gamage
Tarr and Augustus Henry Wonson, of the Firm of Tarr and
Wonson, of Gloucester, Massachusetts, United States of America,
Paint Manufacturers.
Sealed the 18th November 1870, and dated the 6th June 1870.
PROVISIONAL SPECIFICATION left by the said William Robert Lake
at the Office of the Commissioners of Patents, with his Petition,
on the 6th June 1870.
I, WILLIAM ROBERT LAKE, of the "International Patent Office,"
Southampton Buildings, London, Consulting Engineer, do hereby
declare the nature of the said Invention for "AN IMPROVED METALLIC
PAINT FOR PREVENTING THE CORROSION AND FOULING OF SHIPS' BOTTOMS AND OTHER
SURFACES IN WATER," a communication, to be as follows:-
:-
The objects of this Invention are the preservation of iron and wooden
surfaces in sea and other water, and the prevention of the adhesion of

page_text: foreign bodies thereto. These objects are effected by the application of
successive coatings of a paint which can be laid on the surfaces by
means of a brush, which is so compounded as to present a smooth hard
surface in sea or other water at all natural temperatures, and which
forms a durable covering for ships and subaqueous structures that is but 5
slightly affected by the wear and exposure.
This paint has for its basis oxide of copper which is mixed with other
substances and applied as herein-after set forth. The oxide of copper
with other metallic oxides in sea water will form chlorides which are
poisonous to animal and vegetable life. These oxides are mixed in a 1
medium which encloses the particles in such a way as to allow some
chemical action to take place without a too rapid solution of the
poisonous oxides, as the chlorides or oxychlorides are formed in the
saline water.
In carrying this Invention into practice I take about forty gallons of 1
wood tar (preferably the best Stockholm tar) to which I add thirty
gallons of naptha of about 18° B. sp. gr., or so much naptha as shall
render the tar nearly of the consistency of boiled linseed oil. The fluids
are mixed carefully, and about twenty-four hours are allowed for
subsidence; the purified tar mixture is then drawn from the dregs, 2
which may then be drained.
To forty gallons of this purified tar I add about thirty pounds of dry
ochry iron ore (commonly known as bog iron ore) in very fine powder,
which must be thoroughly incorporated with the tar; when this has
been done I add about forty pounds of white arsenic and one hundred 2
and sixty pounds of oxide or sub-oxide of copper, and when the whole is
reduced to a thick paint by a mill or otherwise, the preparation is fit for
use as a protective covering for wood or iron surfaces.
Instead of the above I may take copper ore which has been roasted
till the iron, copper, and arsenic are converted into oxides. I ascertain 3
by analysis the proportions of the oxides present, and by the addition of
pure oxides regulate the proportions nearly as above.
In order to aid the solution of one or more of these oxides in sea
water I sometimes use a small proportion of oxide of zinc.
3
The medium formed from wood tar is found to be the best for the 3
general purpose of painting ships' bottoms and similar surfaces, but
other known media may be used if they are of such a character as to

page_text: properly dissolve and hold the oxides suspended, and not interfere with
their intended action by corrosion. For fresh water, in lieu of the wood
tar, coal tar is preferable, because of its greater varnish-like character. I
may also use the residuary products of the distillation of palm oil or
petroleum oil, both of which have a tar-like character.
When this improved paint is to be applied to a rough surface, such as
the bottom of an iron vessel, or to a rough wood surface it is necessary
that such surface should be first coated with coal tar dissolved in naptha
or with asphaltic varnish.
SPECIFICATION in pursuance of the conditions of the Letters Patent,
filed by the said William Robert Lake in the Great Seal Patent
Office on the 6th December 1870.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, WILLIAM
ROBERT LAKE, of the "International Patent Office," Southampton
Buildings, London, Consulting Engineer, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her
Letters Patent, bearing date the Sixth day of June, in the year
of our Lord One thousand eight hundred and seventy, in the thirty-
third year of Her reign, did, for Herself, Her heirs and successors,.
give and grant unto me, the said William Robert Lake, Her special
licence that I, the said William Robert Lake, my executors, adminis-
trators, and assigns, or such others as I, the said William Robert Lake,
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, exercise, and vend, within the United Kingdom of Great Britain
and Ireland, the Channel Islands, and Isle of Man, an Invention for
"AN IMPROVED METALLIC PAINT FOR PREVENTING THE CORROSION AND FOULING OF
SHIPS' BOTTOMS AND OTHER SURFACES IN WATER," a communication to me
from abroad by James Gamage Tarr and Augustus Henry Wonson, of
the Firm of Tarr and Wonson, of Gloucester, Massachusetts, United
States of America, Paint Manufacturers, upon the condition (amongst
others) that I, the said William Robert Lake, my executors or adminis-
trators, by an instrument in writing under my, or their, or one of their
hands and seals, should particularly describe and ascertain the nature

page_text: of the said Invention, and in what manner the same was to be per-
formed, 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 William Robert Lake, do hereby
declare the nature of the said Invention, and in what manner the
same is to be performed, to be particularly described and ascertained
in and by the following statement :-
The objects of this Invention are the preservation of iron and wooden
surfaces in sea and other water, and the prevention of the adhesion of
barnacles, seaweed, and other substances thereto. These objects are
effected by the application of a paint which can be laid on the surfaces
by means of a brush in the ordinary manner of painting. This paint
has for its basis oxide of copper, which is mixed with other substances
as herein-after set forth.
In carrying this Invention into practice I take about forty gallons of
wood tar (preferably the best Stockholm tar) to which I add thirty
gallons of naphtha of about 18° B. sp. gr., or so much naphtha as shall
render the tar of the consistency or nearly so of boiled linseed oil. The
fluids are mixed carefully, and about twenty-four hours are allowed for
subsidence; the purified tar mixture is then drawn from the dregs,
which may be drained.
To forty gallons of this purified tar I add about thirty pounds of dry
ochrey iron ore (commonly known as bog iron ore) in very fine powder,
which must be thoroughly incorporated with the tar; when this has
been done I add about forty pounds of commercial white arsenic, and
one hundred and sixty pounds of oxide or suboxide of copper, and when
the whole is reduced to a thick paint by a mill or otherwise, the
preparation is ready for use or sale as a protective paint for wood or iron
surfaces.
In making this paint I prefer to use the ordinary copper scales of
commerce, that is to say, the scales produced by rolling and hammering
metallic copper; but do not confine myself to this form of oxide of
copper.
In some cases I may take copper ore which has been roasted till the
iron, copper, and arsenic are converted into oxides more or less perfectly,

page_text: and by the addition of the metallic oxides, regulate the proportions
nearly as above.
The medium or vehicle formed from wood tar with coal tar naphtha is
found to be the best for the general purpose of painting ships' bottoms
and similar surfaces; but other known media may be used if they are of
such a character as to properly dissolve and hold the oxides suspended
and not interfere with their intended action by corrosion or otherwise.
For fresh water in lieu of the wood tar coal tar may be used, and I may
also use the residuary products of the distillation of palm oil or
petroleum, both of which have a tar-like character.
When applying this improved paint to the bottoms of iron ships or
vessels, it is necessary that the iron should be first completely covered
with an intermediate or primary coat of some non-metallic paint, such
as may be made from asphaltum, or the media mentioned above. This
is necessary in order to insure the proper adhesion of my paint, and also
to protect the iron in combination with the metallic paint.
Having thus fully described the said Invention as communicated
to me by my foreign correspondents, and shewn how the same may
be conveniently and advantageously carried into practice, I claim,-
A paint consisting of oxide of copper combined with the other
materials herein specified (or equivalent materials) in or about in the
proportions set forth.
In witness whereof, I, the said William Robert Lake, have here-
unto set my hand and seal, this Sixth day of December, in the
year of our Lord One thousand eight hundred and seventy.
Witness,
E. C. JACKSON.
WILLIAM ROBERT LAKE. (L.S.)