CERTAIN IMPROVEMENTS IN THE MANUFACTURE OF BRONZE AND OTHER METALLIC POWDERS
Year: 1843

page_text: TO ALL TO WHOM THESE PRESENTS SHALL COME, I, HENRY
BESSEMER, of Baxter House, Saint Pancras, in the County of Middlesex,
Engineer, 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 Fifteenth day of June, One thousand eight hundred and
forty-three, in the sixth year of Her reign, did, for Herself, Her heirs and
successors, give and grant unto me, the said Henry Bessemer, Her especial
licence that I, the said Henry Bessemer, my exors, admors, and assigns, or
such others as I, the said Henry Bessemer, my exors, admors, or assigns,
should at any time agree with, and no others, should and lawfully might,
from time to time and at all times during the term of years therein expressed,
make, use, exercise, and vend, within that part of the United Kingdom of
Great Britain and Ireland called England and Wales, and the Town of
Berwick-upon-Tweed, and also the Islands of Jersey, Guernsey, Alderney,
Sark, and Man, and also all the Colonies and Plantations abroad, my said
Invention of "CERTAIN IMPROVEMENTS IN THE MANUFACTURE OF BRONZE AND
OTHER METALLIC POWDERS;" in which said Letters Patent is contained a
proviso obliging me, the said Henry Bessemer, by an instrument in writing
under my hand and seal, particularly to describe and ascertain the nature of
my said Invention, and in what manner the same is to be performed, and
to cause the same to be enrolled in Her said Majesty's High Court of
Chancery within six calendar months next and immediately after the date of
the said recited Letters Patent, as in and by the same, reference being
thereunto had, will more fully and at large appear.

page_text: NOW KNOW YE, that in compliance with the said proviso, I, the said
Henry Bessemer, do hereby declare that the nature of my said Invention
consists in certain improvements in the manufacture of bronze or bronze
powder herein-after mentioned, that is to say :-
In the first place I use oil or other unctious matter in the said manu-
facture; and, secondly, I use certain machinery for the purpose of rubbing,
tearing, or grinding metal leaf in combination with oil or other unctious
matters, and reducing the said metal leaf into fine particles or powder, pro-
ducing thereby what is technically called bronze or bronze powder; and which
process also imparts a more brilliant surface to the particles of bronze than
can be produced by the mode of manufacture hitherto pursued.
And in further compliance with the said proviso, I do hereby describe the
machinery by which the said Invention may be carried into effect, reference
being had to the Drawings annexed, and to the figures, letters, and numbers
marked thereon, that is to say :-
DESCRIPTION OF DRAWINGS.
Figure is a front elevation of my improved grinding machine, shewn in
connexion with certain gearing whereby motion is communicated from a steam
engine or other first mover; Figure 2 is a plan or bird's-eye view of the same;
Figure 3 is an end view. The Figures 1, 2, and 3 are drawn to a scale of half
an inch to the foot, and Figures 4, 5, 6, and 7 are drawn to an enlarged scale,
or one inch to the foot, and Figures 8 and 9 are drawn full size, and are
intended to show more clearly the detail of the machine.. Similar letters of
reference are used to denote similar parts in the whole of these Figures.
A, A, A, is the foundation plate of the machine; B, B, B, are iron columns
firmly bolted on the under side of the plate A, and supporting the upper
framing or entablature C, C, C; D, D, are two shafts supported in plummer
blocks E, E, which shafts overhang the frame at one end, and carry the large
spur wheels F, F, to which motion is communicated by the small spur wheel
G, which is fitted to the shaft H of a steam engine or other first mover.
Near the centre of the shafts D, D, are fitted the bevil wheels I, I, which
communicate motion to the upright shafts J, J, by means of the bevil pinions
K, K. The lower part of the upright shafts are formed into a cone, and are
case-hardened, and work into corresponding conical opening in the hardened
steel step L, in the centre of the steel bed N, which is formed of seven pieces or
blocks of steel 1, 2, 3, 4, 5, 6, and 7, accurately fitted together, and screwed
to a circular disc M, M. The block L 1 forms the step in which the shaft J
works. These steel blocks are more clearly shewn in Figures 6 and 7, where

page_text: the blocks 1, 2, 3, 4, 5, and 6, which compose the steel bed N, are shewn as
fixed together, and the block 7, Figure 7, is shewn as detached, to better
illustrate their form and the way in which they are placed together. In order
to secure these blocks more firmly, and to fix them to the bed A of the
machine, they are surrounded by the ring O, O, which is made hot, and
allowed to cool and shrink tight up to them. This ring O has a flange at the
lower edge, by which it is bolted to the bedplate A, ànd the upper edge is
formed into a channel surrounding the bed N, and forming a sort of trough,
with a spout P to convey any fluid that may flow over the edge of the steel
bed N into a receptacle Q placed to receive it. The steel bed N is fluted or
grooved in radial lines extending from the step L 1 to the periphery. These
grooves are rounded off at top and bottom, and form in section a sort of waved
line, seen more clearly at Figure 8. The grooves are highly polished, and
the steel of which the blocks are formed is hardened and tempered, and forms
a bed of five feet diameter. Above this bed is placed the rod drum R, R,
made of gun metal. The boss of the drum is bored out to receive the lower
end of the shaft J, J, to which it is firmly keyed. This boss is surrounded by
a small cylinder T, through which the arms U, U, pass, and unite the outer
drum R, R, with the boss. V, V, are four openings through which the
materials pass from the hopper W on to the steel bed N. The four arms
U, U, are not continued in a straight line from the centre of the drum towards
its periphery, but are formed into a sort of crank-like recess for purposes
hereafter to be described. The whole of the spaces X, X, are filled with
straight rods of steel, which are cylindrical, and have their lower ends rounded,
hardened, and polished. The four spaces X, X, contain about 49,240 such rods,
of a quarter of an inch diameter and twenty-two inches long, and of six ounces
weight each, making in all about 18,450 pounds weight. These rods fit very
close and compact, as shewn at Figure 9, and rest their polished ends on the
undulating surface of the steel bed N. Now it will be seen that as the shaft
J and drum R revolve, the whole of the rods are thereby put in motion, and
rotate round about the centre L, and rise and fall as they pass in succession
over the grooved surface of the bed N.
.
In Figures 1 and 2 I have shewn two of these grinding machines, which I
have described together, as they are made precisely similar, excepting that
the steel rods used in one are of only half the diameter of those already
described, or of an eighth of an inch each. This is found preferable as a
finishing machine, as it gives four times the number of rods, each of which
weighs only one fourth as much as those before described.
..

page_text: In Figure 1 I have shewn one of the grinding machines in elevation and
the other partly in section, and in Figure 2 I have removed part of the shaft
D and its bevil wheel I, and that part of the frame C in which the upper part:
of the shaft J works, in order to shew more clearly the upper surface of the
rods contained in the spaces X, X.
I will now describe the method of operating with the said machine when;
used for making "Bronze or other Metallic Powders." The metal, or such
particular alloys of metal as may be required, are first reduced to a very thin
leaf by beating between skins, as practised by goldbeaters and makers of what
is called Dutch metal, and as already practised by bronze-powder manufac-
turers. When the metal leaf has been extended to such a degree of thinness
that one pound averdupois is equal to about 850 superficial feet, I put it into.
an iron-wire sieve of ten meshes to the inch. Olive oil is allowed to flow
from a stopcock placed above the centre of the sieve into the leaf metal, which
is now to be briskly moved over the surface of the sieve by a wire brush until
the whole of the leaf is thereby forced through the sieve into a receptacle
below. Thus prepared, the small fragments of leaf metal, with about its own.
weight of oil, are introduced into the hopper W of the machine, where,
sinking by its own gravity, it passes down the opening V, V, until it reaches
the centre of the bed N, where it spreads itself, and partly flows between and
among the steel rods, and by the centrifugal force acquired by their rotation
it is gradually forced towards the periphery, where it finally escapes into the
trough O. In its progress the whole mass has been passed over by many thou-
sands of the polished spherical ends of the rods, acting upon it in every variety
of position, as they ascend and descend the corrugated surface N, and by
a sort of tearing and burnishing operation separate the coarse pieces of leaf
into innumerable small polished particles. In passing through the machine
three times the metal will be reduced to the coarse sorts of bronze, and
passing through the machine six or eight times, the fine sorts, which should
only receive three workings by the large rods, and then be put into the hopper
of the machine containing the small rods, which, by their more gentle action,
produce a more brilliant and regular powder. It will be understood that
there are no rods resting on the bed N at those parts over which the arms
U, U, are passing; and as this would form a passage whereby the fluid
materials might flow uninterruptedly into the trough, I have made a recess or
bend in the arms U, U, which, forming part of the space X, is filled with rods,
and thereby intercepts the passage of the materials, and causes them to pass
between and under the rods, instead of escaping by a straight passage, under

page_text: AND BE IT REMEMBERED, that on the Fifteenth day of December,
in the year of our Lord 1843, the aforesaid Henry Bessemer came before our
said Lady the Queen in Her Chancery, and acknowledged the Specification
aforesaid, 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.
Enrolled the Fifteenth day of December, in the year of our Lord One
thousand eight hundred and forty-three.