AN IMPROVEMENT IN THE MAKING OR MANUFACTURING OF GREEN PAINT
Year: 1812

page_text: TO ALL TO WHOM THESE PRESENTS SHALL COME, I, WILLIAM
PARKER, of Whitechapel, in the County of Middlesex, Oil and Colourman;
send greeting.
WHEREAS His most Excellent Majesty King George the Third did, by
His Letters Patent, under the Great Seal of the United Kingdom of Great
Britain and Ireland, bearing date at Westminster, the Tenth day of August, in
the fifty-second year of His reign, give and grant unto me, the said William
Parker, my executors, administrators, and assigns, His special licence, full
power,. sole privilege, and authority, that I, the said William Parker, my
executors, administrators, and assigns, during the term of fourteen years.
therein mentioned, should and lawfully might make, use, exercise, and vend,
within England and Wales, and the Town of Berwick-upon Tweed, my In-
vention and discovery of "AN IMPROVEMENT IN THE MAKING OR MANUFACTURING
OF GREEN PAINT;" in which said Letters Patent there is contained a proviso
obliging me, the said William Parker, by an instrument in writing under
my hand and seal, to cause a particular description of the nature of my said
Invention, and in what manner the same is to be performed, to be inrolled in
His Majesty's High Court of Chancery within one calendar month after the
date of the said recited Letters Patent, as in and by the same, relation being
thereunto had, may more fully and at large appear.
NOW KNOW YE, that, in compliance with the said proviso, I, the said
William Parker, do hereby declare that my.said Invention consists in combining

page_text: fixed alkali with mineral oxide and precipitate of copper, and thereby pro-
ducing a permanent pea green colour for house and ship painting, and is not
liable to decomposition by salt water, which I prepare in the following
manner, that is to say:-
Take fourteen ounces of crude potash, fourteen drams of crude white
arsenic, boil them in two gallons of soft water until quite dissolved, then put
the liquor into a cast-iron vessel to cool and settle, draw off the liquor clear
from the seditment, and put it into a vessel that will hold twenty gallons, and
to it six gallons of clear soft water, cold. Take one pound of Roman vitriol,
and boil in two gallons of soft water till dissolved; put the solution into an
open vessel till quite cold, then to be added gradually to the aforesaid solution
of fixed alkali, stirring it well all the time, which will produce a genuine green
oxide, then to proceed in the usual way of mineral green. A most essential
part of this preparation is to make the mineral green without using caustic
alkali, which is the general way of manufacturing it; for this purpose the
caustic alkali acts too powerful on the vegetable quality of linseed oil used in
this preparation, and thereby rendering it mucilaginous.
Preparation of precipitate of copper, to mix with the aforesaid oxide, viz*:-
Take one pound of Roman vitriol, and boil it till dissolved in two gallons of soft
water; at the same time dissolve in another vessel half a pound of the first sort
of America pearlash, put the solution of vitriol, boiling hot, into a vessel that
will hold ten or twelve gallons, then add to it gradually the solution of pearlash,
boiling hot, to .be well stirred all the time; on mixing the solution together it
will cause a strong effervescence; if the pearlash is good, it will be enough to
precipitate the vitriol, which will be known by the effervescence immediately
subsiding and the precipitate falling to the bottom of the vessel, and thereby
producing a fine green colour; when settled, draw off the clear liquor, then put
it into bags made of canvas to filter, and when well drained to be laid on chalk
stones to draw a further quantity from it; then to be put into a stove to dry.
Preparation of mixing or combining with mineral substances in linseed
oil: Take one pound of the genuine mineral green, prepared as herein
described, to be well powdered, 'one pound of the precipitate of copper, one
pound and a half of refiners' blue verditta, three pounds of white lead, dry
powdered; three ounces of sugar of lead, powdered fine; the whole of those
ingredients to be mixed up in linseed oil and ground in a levigating mill,
passing it through until quite fine; it will thereby produce a bright mineral
pea green paint, will preserve a blue tint, will keep any length of time in any
climate without injury, by putting oil or water over it.
Directions for using the said colour for house or ship painting-Take one

page_text: pound of the green colour paint prepared as aforesaid, with one gill of pale boiled
oil, mix them well together; this will produce a strong pea green paint; the tint
may be varied at pleasure, by adding a further quantity of white lead ground in
linseed oil. This colour will stand the weather, and resist salt water; it may also
be used for flatting rooms, by adding three pounds of white lead ground in half
linseed oil and half turpentine to one pound of the green, then to be mixed up
in turpentine spirits, fit for use; it may also be used for painting venetion
window blinds, by adding to one pound of the green paint ten ounces of white
lead ground in turpentine, then to be mixed up with turpentine varnish for
use. In all the aforesaid preparations it will retain a blue tint, which is very
desirable; when used for blinds a small quantity of Dutch pink may be put to
the white lead, if the colour is required of a yellow cast.
In witness whereof, I, the said William Parker, have hereunto set my
hand and seal, the Eighth day of September, One thousand eight
in the year above mentioned, the aforesaid William Parker came before our
Lord the King in His Chancery, and acknowledged the Specification aforesaid,
and all and every thing therein contained, in form above written. And
also the Specification aforesaid was stamped according to the tenor of the
Statute in that case made and provided.
Inrolled the same Eighth day of September in the year above written.