IMPROVEMENTS IN THE MANUFACTURE OF OXIDE OF LEAD. AND ITS SALTS
Year: 1857

page_text: LETTERS PATENT to Charles Edward Symonds, of No. 56, Stones End,
Borough of Southwark, Paint and Color Manufacturer, for the Invention
66
-- an nin
Sealed the 24th July 1857, and dated the 29th January 1857.
PROVISIONAL SPECIFICATION left by the said Charles Edward Symonds
at the Office of the Commissioners of Patents, with his Petition, on the
29th January 1857.
I, CHARLES EDWARD SYMONDS, of No. 56, Stones End, Borough of
Southwark, Paint and Color Manufacturer, do hereby declare the nature of
the said Invention for "IMPROVEMENTS IN THE MANUFACTURE OF OXIDE OF LEAD.
AND ITS SALTS," to be as follows:-
I take chloride of lead which I mix with a hot solution of caustic barytes,
or other earth, whereby I obtain a solution of chloride of barium or other
earth with a precipitate of oxide of lead. I then separate and wash the oxide
of lead and digest it with the proper acid to form the salt of lead I require..

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent, filed
by the said Charles Edward Symonds in the Great Seal Patent Office
on the 27th July 1857.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, CHARLES
EDWARD SYMONDS, of No. 56, Stones End, Borough of Southwark, Paint and
Color Manufacturer, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her Letters
Patent, bearing date the Twenty-ninth day of January, in the year of our Lord
One thousand eight hundred and fifty-seven, in the twentieth year of Her reign,
did, for Herself, Her heirs and successors, give and grant unto me, the said
Charles Edward Symonds, Her special licence that I, the said Charles Edward
Symonds, my executors, administrators, and assigns, or such others as I, the
said Charles Edward Symonds, 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 "IMPROVEMENTS IN THE MANUFACTURE OF OXIDE OF LEAD AND ITS SALTS,"
upon
the condition (amongst others) that he, the said Charles Edward Symonds,
his executors or administrators, by an instrument in writing under his 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, tho said Charles Edward Symonds, 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 statement:―
My Invention consists in a mode of producing oxide of lead from chloride
of lead by mixing chloride of lead with caustic barytes, caustic lime, or
caustic magnesia, or mixtures of these earths. This oxide of lead so produced
may then be used, either by itself, or combined with acids, to form salts of lead.
I prefer to use caustic barytes in practice. To effect this operation, I take an
equivalent of chloride of lead (that is 139 parts) and I mix with it intimately
an equivalent of any one of the above earths, which, if barytes were employed,
would be 77 parts, I then add water to the mixture and allow it to boil a
short time. The result is a solution of chloride of barium and a precipitate

page_text: of oxide of lead, mixed sometimes with a small quantity of oxychloride of
lead. The solution of chloride of barium is then poured off and the residual
oxide of lead well washed, after which it may be dissolved in acetic, nitric, or
other acid, in order to form solutions of acetate, nitrate, or other salt of lead.
These solutions are then evaporated in the ordinary way, and the resulting
salts obtained.
I claim, firstly, the method of decomposing chloride of lead by caustic
barytes, caustic lime, or caustic magnesia, separately or combined.
Secondly, I claim the use of oxide of lead procured by the decomposition of
chloride of lead, by means of caustic barytes, caustic lime, or caustic magnesia,
separately or combined.
Lastly, I claim the manufacture of salts of lead, such as the acetate or
nitrate, from oxide of lead, procured from the decomposition of chloride of lead
by caustic barytes, caustic lime, or caustic magnesia, separately or combined.
In witness whereof, I, the said Charles Edward Symonds, have hereunto
set my hand and seal, this Twenty-seventh day of July, in the year
of our Lord One thousand eight hundred and fifty-seven.
CHAB E. SYMONDS. (L.S.)