AN IMPROVED METHOD OF MANUFACTURING WHITE LEAD
Year: 1858

page_text: LETTERS PATENT to George W. Burton, of Dubuque, in the State of
Iowa, United States of America, for the Invention of "AN IMPROVED
METHOD OF MANUFACTURING WHITE LEAD."-A communication.
Sealed the 21st May 1858, and dated the 11th February 1858.
PROVISIONAL SPECIFICATION left by the said George W. Burton at
the Office of the Commissioners of Patents, with his Petition, on the
11th February 1858.
I, GEORGE W..Burton, of Dubuque, in the State of Iowa, United States of
America, do hereby declare the nature of the said Invention for "AN IMPROVED
METHOD OF MANUFACTURING WHITE LEAD," to be as follows:-
This Invention of an improved method of manufacturing white lead
consists in subjecting the lead to the action of steam and atmospheric air for
the purpose of oxydation, thien to the vapor of acetic acid in order to form
the sub-acetate, and afterwards to the action of carbonic acid, alternately and
successively until the operation is complete, whereby the metal becomes
carbonated in a more speedy, regular, and effectual manner than when the
metal is exposed to the action of the air, vapour of hydrated acetic acid, and
carbonic acid conjointly.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent, filed
by the said George W. Burton in the Great Seal Patent Office on the
10th August 1858.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, GEORGE
W. BURTON, of Dubuque, in the State of Iowa, United States of America,
send greeting.
.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her Letters
Patent, bearing date the Eleventh day of February, A.D. 1858, in the twenty-
first year of Her reign, did, for Herself, Her heirs and successors, give and
grant unto me, the said George W. Burton, Her special license, that I, the
said George W. Burton, my executors, administrators, and assigns, or such
others as I, the said George W. Burton, 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 METHOD OF MANUFACTURING WHITE LEAD," upon the condition
(amongst others) that I, the said George W. Burton, by an instrument in
writing under my hand and seal, 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 mouths next and immediately after the date of the said
Letters Patent.
NOW KNOW YE, that I, the said George W. Burton, do hereby declare
the nature of my said Invention, and in what manner the same is to be per-
formed, to be particularly described and ascertained in and by the following
statement, reference being had to the Drawing hereunto annexed, and to the
letters and figures marked thereon (that is to say) :-
This improvevement consists in subjecting the lead to theactionofsteam and
atmospheric air for the purpose of oxydation, then to the vapour of acetic acid
in order to form the sub-acetate, and afterwards to the action of carbonic acid
alternately and successively, until the operation is complete, whereby the metal
becomes carbonated in a more speedy, regular, and effectual manner than
where the metal is exposed to the action of the air, vapour of hydrated acetic
acid, aud carbonic acid conjointly.
In order to show how this process may be carried into effect, I will now
proceed to describe an apparatus suitable for such a purpose.
In the Drawing, Figure 1 represents a plan of such an apparatus, the top of

page_text: ;
one chamber being removed to exhibit the arrangement of the parts of the
interior, the top and slats of another chamber being also removed to show the
arrangement of pipes for the admission of steam and the vapour of acetic acid
Figure 2 represents an end view of the same; Figure 3 represents a vertical
longitudinal section, taken through the line a, a, of Figure 1; and Figure 4
represents a vertical transverse section through the line X, X, of Figure 1.
(A & A¹) represent two series of quadrangular wooden chambers of any
desired number, arranged and running parallel with each other. Through the
lower part of each chamber is passed a pipe (B), which connects at one end
with the main pipe (C), leading from the boiler (D) that contains the acetic
acid, and at the o'her end with the steam pipe (E) leading from the boiler (F).
Each of these pipes is provided with stop cocks (e), by means of which the
steam and vapours may be admitted to the room or shut off, as desired, from
the pipe (B); two series of pipes (a) branch out on either side parallel with the
bottom of the chambers and extending nearly to their sides; through these
pipes are pierced a number of holes, a row on each side, and one on the top
for the purpose of distributing through the chamber the vapours admitted into
the main pipe (B).. Into each of these chambers, commencing a little above
the pipes (a) are arranged a series of ranges or slats (b), at a suitable distance
apart for the reception of the coils of lead, and upon which they are placed, a
small space in the centre of the chamber being reserved for a chimney (c)
consisting of a tube formed of any suitable material, and pierced with a
number of holes for the emission of the vapours from the room, and by which
they are carried into the open air. By means of this chimney the vapours or
gases are equally diffused throughout the chambers by means of a valve (d)
fitted to its mouth, inasmuch as when the valve is closed the cold air on the
outside acting upon the walls of the chambers draws the vapours towards them
and condenses them; but by opening the valve (d) a draft is immediately.
created in the room and the gases drawn towards its centre. Through the top
of the chambers are pierced several holes (f), in this instance four in number,
each of which is furnished with a valve (g) attached to each other in pairs, by
means of connecting rods (), the object of which is to enable the operatives to
permit or prevent the escape of the gases or vapours, as required. The sides
of the chambers near the bottom are also pierced with a number of holes (i)
provided with stoppers or valves, by means of which the admission of air or
the escape of gases, if thought advisable, is regulated. Upon the sides of the
chambers, facing each other and near their top, are arranged main pipes (G)
cominunicating with and leading from a gas chamber or reservoir (H); from
this pipe branch pipes (1) lead into the upper part of the chambers through

page_text: which the carbonic acid gas is carried from the reservoir (H) as it is generated
from the furnace (K), (which may or may not generate the steam or vapour
of acetic acid), and diffused throughout the chamber, it having a tendency to
fall towards the bottom by virtue of its superior specific gravity. Each of the
branch pipes (I) are provided with stop-cocks (n), by means of which the
supply is regulated or cut off, as required. The furnace (K), which generates
the carbonic acid, is furnished with two chimneys and slides or valves for each,
one (L) leading into the open air, and the other into the gas chamber (FI), so
that when a fresh supply of fuel has been added to the furnace the chimney
leading to the chamber may be closed by its valve until all the smoke com-
mingled with impurities has been driven off through the chimney leading to
the atmosphere, after which the valve of the latter is closed, and that of the
former opened for the admission and collection of the gas, whence it is carried
and diffused throughout, the chambers (A & A¹) bymeans of the main (G)and
branch pipes (I), as before described. Each of these chambers is provided
with a door (J), by means of which the operatives effect an entrance either to
supply fresh lead to undergo the process, or to take away that which has
already undergone it, for the purpose of grinding &c., &c. ; these doors are
made to fit with great exactness to prevent the escape of the gases, and are
secured by means of cross bars P, or in any other suitable manner. In each
door is placed a plate of glass, there being others arranged in the rear side of
each chamber to enable the attendants to watch the progress of the process.
In order to keep up the requisite temperature of the room, a steam chamber
may be formed underneath the bottoms of the chambers, into which steam
may be passed either directly from the boiler (F) or from the steam pipe (E)
that supplies the chambers. From the foregoing description of the apparatus
my process will be easily understood, to wit, the rolls or coils of lead having
been arranged upon the slats (b), and the doors (J) and valves (g) closed, the
plugs or valves of the air holes (1) are opened, and the stop-cocks (e) of the
steam pipes (E) turned to give free ingress to the steam, which passing along
the pipe (B) into the perforated branch pipes (a), is diffused throughout the
chambers; they are left in this condition until a thick coating of the oxyde
has been formed; the steam is then shut off and the valves (g) opened for a
short time to permit its escape,and then closed, after which the stop-cocks (e)
of the pipes (C) are turned, which permits the vapour of the acetic acid to
enter the pipe(B)and be diffused in the same manner as the steam throughout
the chambers, which immediately commences to act upon the oxyde forming
the sub-acetate of lead. Immediately upon the completion of this part of the
process, sufficient time having been allowed for that purpose, the acetic

page_text: vapours are shut off by turning the stop-cocks (e), and the valves (g) again
opened to permit their escape and again closed, and the carbonic acid gas
permitted to enter by turning the stop-cock (n) of the pipe (G) leading from.
the gas chamber (H). The carbonic acid gas speedily decomposes the acetate
forming the caroonate of lead, after which it in turn is shut off and the valves
opened to permit its escape, and then the steam and air again admitted, and
so on alternately and successively until the whole has become carbonated,
after which it is removed and a fresh supply put in its place to undergo the
same operation.
What I claim as new improvement, and desire to secure by Letters Patent,
is, subjecting the lead and the compounds formed therefrom, by the agents
employed for this purpose, to the action of steam and air, vapeur of acetic acid
andcarbonic acid gas,alternately and successively until the process is complete,
in the manner substantially as and for the purposes set forth. I also claim
the means by which this is effected as arranged and combined..
In witness whereof, I, the said George W. Burton, have heretofore set
my hand and seal, the Twelfth day of July, One thousand eight
hundred and fifty-eight.
GEO. W. BURTON. (L.S.)