IMPROVEMENTS IN THE MANUFACTURE OF WHITE LEAD
Year: 1841

page_text: TO ALL TO WHOM THESE PRESENTS SHALL COME, I, GEORGE
WILDES, of Coleman Street, in the City of London, Merchant, send greeting.
WHEREAS Her present most Excellent Majesty Queen Victoria, by Her
Letters Patent under the Great Seal of Great Britain, bearing date at
Westminster, the Fourth day of September, in the fifth year of Her reign,
did, for Herself, Her heirs and successors, give and grant unto me, the said
George Wildes, Her especial licence, full power, sole privilège and authority,
that I, the said George Wildes, my exors, admors, and assigns, or such others
as I, the said George Wildes, my exors, adñors, or assigns, should at any
time agree with, and no others, from time to time and at all times during
the term of years therein expressed, should and lawfully might make, use,
exercise, and vend, within England, Wales, and the Town of Berwick-upon-
Tweed, the Invention of "IMPROVEMENTS IN THE MANUFACTURE OF WHITE
LEAD," communicated to me by a certain Foreigner residing abroad; in which
said Letters Patent is contained a proviso that I, the said George Wildes,
shall cause a particular description of the nature of the said Invention, and.
in what manner the same is to be performed, to be inrolled in Her said
Majesty's High Court of Chancery within six calendar months next and
immediately after the date of the said in part recited Letters Patent, as in

page_text: and by the same, reference being thereunto had, will more fully and at large
appear.
NOW KNOW YE, that in compliance with the said proviso, I, the said
George Wildes, do hereby declare the nature of the said Invention to consist
in making carbonate of lead, commonly called white lead, by attrition of
metallic lead-inclosed vessels, which vessels are partially filled with water,
carbonic acid gas, atmospheric air, and granulated lead. And in further com-
pliance with the said proviso, I, the said George Wildes, do hereby declare
the manner in which the said Invention is to be performed by the following
statement thereof; (that is to say) :-
The ordinary lead of commerce is melted and poured through a metallic
sieve into water; two hundred pounds weight of the lead thus granulated, or.
a greater or less quantity if preferred, is then placed into a cylindrical,
hexagonal, or square vessel, shaped like a shallow tub, made of wood, and
Jined with sheet lead. A hollow axis goes through the centre of the bottom of
this tub, being fastened to it, so that when the tub revolves the axis revolves
with it; at its other extremity the axis communicates with a generator of
carbonic acid gas and with the interior of the tub. This tub is then placed
so that the plane of its bottom forms an angle of forty degrees, or more or less,
with the horizon, and by any convenient application of power is made partly
to revolve at the rate of twelve or fourteen times per minute. The inclination
and the motion of the tubs are to be such that the piece of lead being carried
by the revolution of the tub to its upper side will roll down again over the
surface of the bottom...The granulated lead being placed in a tub, a sufficient
quantity of water must be added; being about half as much as the tub will
cóntain in its inclined position. Carbonic acid igas is introduced through the
hollow axis, the lid or cover is put on, and the tub caused to revolve at the
rate above given. The supply of gas must be regulated by observation. In
twenty-four hours; or in less time, a large quantity of white lead in water will
have been formed, which is to be drawn. off in..vats, thence,, if advisable,
washed 'and then dried, ground, and packed for use in the ordinary way.
I do not claim as the said 'Invention the use of metallic lead in the form of
granulated lead made by casting melted lead into water, nor the conversion
of metallic lead into a white, product: by attrition in water, nor the use
of any particular form of machinery for causing the attrition in water; but
I do claim as the said Invention the formation of pure carbonate, of lead,
known to painters as good. white lead; by the attrition of lead in water in
closed vessels supplied with carbonic acid gas, and the peculiar adaptation of
the means above described to effect this..object, to wit, a shallow tub with a

page_text: hollow axis placed and revolved in: the position above described, and supplied
with the ingredients above mentioned.
In witness whereof, I, the said George Wildes, have hereunto set my
band and seal, this Twenty-third day of February, in the year of
our Lord One thousand eight hundred and forty-two.
AND BE IT REMEMBERED, that on the Twenty-third day of February, in
the year of our Lord 1842, the aforesaid George Wildes came before our said
Lady the Queen in Her Chancery, and acknowledged the Specification afore-
said, and all and every thing therein contained and specified, in form above
written. And also the Specification aforesaid was stamped according to the
tenor of the Statute made for that purpose.
Inrolled the Fourth day of March, in the year of our Lord One thousand
eight hundred and forty-two.