IMPROVEMENTS IN PROCESSES AND APPARATUS FOR MANUFAC- TURING BRUSHES
Year: 1877

page_text: LETTERS PATENT to Sydney Pitt, of Sutton, in the County of Surrey, for the
Invention of "IMPROVEMENTS IN PROCESSES AND APPARATUS FOR MANUFAC-
TURING BRUSHES." A communication from abroad by Isaiah Smith Hyatt, of
Newark, in the County of Essex, and State of New Jersey, United States of
America, Manufacturer.
Sealed the 30th November 1877, and dated the 6th October 1877.
COMPLETE SPECIFICATION filed by the said Sydney Pitt at the Office of
44
IMPROVEMENTS IN PROCESSES
A communication from abroad
the Commissioners of Patents on the 6th October 1877.
SYDNEY PITT, of Sutton, in the County of Surrey.
AND APPARATUS FOR MANUFACTURING BRUSHES."
by Isaiah Smith Hyatt, of Newark, in the County of Essex, and State of New
Jersey, United States of America, Manufacturer.
The Invention appertains to that class of processes and apparatus in and by
means of which brushes are made with tufts of bristles secured in the body of the
brush, which body is composed either wholly or partly of a substance or material
susceptible of being rendered plastic by heat.
It is contemplated to use celluloid, and I shall describe the Invention in this
Specification as applied especially in the use of that material, but any other
substance or material which has in common with celluloid the characteristics of the
requisite hardness for the preliminary, for some of the intermediate, and for the
final conditions of the manufacture, and the requisite capability of being softened
and rendered plastic in the primary and in some of the intermediate stages of the
process of manufacture, as herein-after more fully specified, may also be employed.
The process of manufacturing such brushes as are above indicated consists in
forming the material by means of suitable moulds into two parts, which I designate
as half shells, perforating one of these moulded half shells with a series of holes for
the tufts of bristles (these holes being in number and relative arrangement such as
is conformable to the shape and purpose of the particular brush to be made), tufting
the bristles in the perforated half shell, giving the tufted bristles the proper inclina-
tion and relative protrusions on the respective sides of the perforated half shell,

page_text: securing the inner ends of the bristles by matting or ironing them down upon the
under side of the perforated half shell, superimposing upon the matted ends of the
bristles a thin sheet of plastic material, which shall further secure the bristles and
keep them in place and in position, covering this sheet of plastic material with a
wooden core, which extends also into the handle of the brush, and imparts strength
(at less expense than would attend the use of a solid mass of the plastic material);
again, covering this wooden core with the other (unperforated) half shell, which
forms the back of the brush, and subjecting all these parts to heat and pressure in a
die, so as to mould and compress the superimposed sheet upon and about the matted
or ironed ends of the bristles, to compress and condense the two half shells upon
and about the superimposed sheet and wooden core, and to weld the superimposed
sheet and the shells together, as well as to compact and more effectually close the
holes in the perforated half shell about the tufts of bristles, the bristles being
thoroughly supported and protected throughout the process.
There is thus obtained, as the product of the improved process and without
moulding the material upon the bristles by hand, a strong, cheap, durable brush, in
which there are no seams or joints to open in the course of its use, no cement to
crumble and admit moisture which would induce disintegration, and no threads or
wires to break off or rust out, and thereby loosen the bristles.
By the improvements one is also enabled to give to the outer ends of the bristles,
in a better manner than heretofore, that unevenness of surface which is requisite to
ensure their proper penetration in use.
The apparatus involved in this process comprises a sectional tufting block, which
has a depth greater than the length of the bristles above the surface of the brush,
and is provided with a series of peculiarly adapted holes, corresponding in their
number, in their inclination, and in their relative arrangement with the holes in the
perforated half shell, thereby determining the number, the inclination, and the
relative arrangement of the tufts of bristles in the finished brush, and also supporting
and protecting the bristles during the process of the manufacture.
This tufting block is made in two horizontal sections, the lower section having
its under surface and the perforations through it corresponding with the convex
surface of the perforated half shell and with the perforations through it. The holes
in this lower section are inclined outwardly from bottom to top conformably with
the inclinations or angles of divergence desired to be given to the tufts of bristles
in the finished brush, and are chamfered out on the upper surface for purposes to be
presently described.
The upper section of this tufting block has an under surface to correspond with
the upper surface of the lower section, and the holes through it are inclined from
bottom to top conformably with the holes through the lower section and through
the perforated half shell. The holes through this upper section of the tufting block
are chamfered on its lower surface to correspond with the chamfered holes in the
upper surface of the lower section, and thus when the two sections are in position
one upon the other, the holes through the tufting block are inclined from top to
bottom, each at the desired angle of divergence for the respective tufts of bristles
in the finished brush and coincident with the perforations through the half shell.
These holes through the tufting block are small at the upper and lower surfaces of
the block.
The purposes of the enlargements or chamfers in the middle of the block, as
above stated, will presently be described.
The outline of the upper section of this tufting block is a continuation of the 5
outline of the lower section, both conforming to the intended outline to be imparted
to the bristles in the finished brush.
Some further features of the improvements in the apparatus for the practice of
the improved process will be particularized herein-after.
In the accompanying Drawings, which form part of this Specification, I illustrate 5
the process by which a hair brush of celluloid is made.
Figure 1 is a plan of one of the half shells, which is inverted to show its

page_text: concavity, and the surrounding upright flange or wall, more distinctly shown in
Figure 2, which is a longitudinal section of Figure 1.
The irregular outline seen in Figure 1, and the thin projections f shown in
Figure 2, indicate the fin or strip of surplus material which is forced out between
the halves of the mould in which the half shell is formed, which mould has bearing
surfaces (instead of cutting edges) to ensure the back pressure essential in moulding
celluloid, as is well understood by those skilled in the manipulation of that or
similar material,
The bead b seen in Figure 2 is provided for the purpose of affording the perforated
half shells a suitable support in the finishing die, as will be herein-after explained.
The mould, being as usual a mere counterpart of the half shell to be formed in it,
will of course vary in its internal shape according to the form of the brush to be
made. It must be made in two parts, and have the usual provision for the escape
of surplus material, such as a groove or bevels, outside of the bearing surfaces, as is
well understood by those who make or use such moulds.
Figure 3 is a plan of a half shell with its convex side uppermost, and perforated
with holes, the number and relative positions of which determine the number and
position of the tufts of bristles in the finished brush. These half shells are moulded
as are other forms of celluloid, that is to say, an approximate form of the material
is cut out of a sheet or mass of the proper thickness and placed between the two
halves of the mould above described, and the mould thus "packed" is subjected to
heat under suitable pressure, both the heat and the pressure being gradually applied.
as the material becomes plastic until the two halves of the mould are brought
together, or as nearly together as is possible, with the fin of surplus material between
them, and at this point the shaping of the half shell is completed, as shown in
Figure 1. The heat is then shut off, but the pressure maintained, while the mould
is cooled, when it is removed from the press, and the half shell, with its fin f and
bead b, is ready to be used as a top piece or back, or to be perforated and tufted
with bristles.
The half shell intended for the face of the brush is while cold and hard placed
upon a die of a form corresponding with that of the concavity in the half shell, and
perforated conformably with the holes to be made in the shell, the convex side of
the half shell being uppermost, while its concave side fits over and rests flat upon
the perforated die, and a series of punches corresponding in number, and relative
arrangement with the number, and relative arrangement of the holes in the die,
and of the tufts of bristles to be put in the brush is brought down upon the shell,
perforating it at one operation, as shown in Figure 3, with the required number of
holes in the required relation to each other. These holes are punched at the
inclination desired to be imparted to the bristles in the finished brush.
The insertion of the bristles is the next step in the process, and for this operation
the perforated half shell is placed with its convex side uppermost upon a flat
surface, and upon this upper surface of the perforated half shell is placed the lower
section of the tufting block, already referred to.
Figure 4 shows a plan of this lower section, the holes through which are
chamfered on its upper surface, as shown in this Figure, while on its under surface-
these holes are small (and not chamfered), as is seen in Figure 5, which is a plan of
the upper súrface of the upper section of the tufting block. The holes through this
upper section of the block are, as is seen, sinall (and not chamfered) on its
upper surface, while on the under surface of this section these holes are chamfered
to correspond with the chamfers on the upper surface of the lower section of the
block.
When in the course of the process the upper section, Figure 5, is placed upon the
lower section, Figure 4, the holes through the two sections will coincide, the entire
series extending through the block; and these holes, while at the top of the upper
section, and at the bottom of the lower section of only about the size of the
intended tufts of bristles, will be at the central part of the block considerably

page_text: t
enlarged for a short distance each way, as is seen in Figure 6, which is a section
through the block when its two parts are in the position described.
As already mentioned, the depth of these holes through the block should be
somewhat greater than the distance to which the longest bristles will reach in these
holes, so that the bristles will be supported and protected during the various stages
of the process. These sections of the tufting block are not however both placed at
once in this position, but on the contrary after the perforated half shell has been
placed upon the flat surface the lower section alone is placed upon the convex
surface of the balf shell, as already stated, with its chamfered surface uppermost,
the series of holes in the half shell coinciding in number and in relative arrangement
with the holes in the block.
It will be seen by referring to Figure 7, which is a section through the perforated
shell, the lower section of the tufting block and the tufts of bristles, that the
bristles can readily be inserted in the chamfered holes in the block section, and
through this section into and through the holes in the half shell, the enlargements
of the holes at the top of the block section facilitating the insertion, while the
smaller continuations of the holes through the section and through the half shell.
give a slight pinch upon the tufts, which suffices to hold the bristles temporarily
in position.
To prevent accidental displacement of the lower section of the block or of the
half shell beneach it a pin is dropped through one of the holes at each end of the
section and half shell, and when the greater part of the holes have been filled with
bristles these pins are removed, they being no longer necessary, and the holes
through which the pins had been inserted are tufted with bristles.
Here I may remark that it is well understood that the surface of the bristles in
a hair brush should be uneven to secure the taking hold, or as it is technically
termed the "penetration" of the bristles when the brush is being used. To ensure
this the bristles are prepared by cutting them into three or more slightly different
lengths, adapted to the desired variations in the surface of the brush, and mixing
these lengths together, so that the quantity taken up from the mixed mass for each
tuft will comprise more or less of each of these lengths, and there will consequently
be no waste from having to trim them off at any stage of the process, nor after the
brush is finished.
The bristles are inserted by a hand, using a pair of gauged nippers, to ensure
substantial uniformity in the number of bristles in the several tufts, and taking care
to fill each of the holes so full as to prevent the bristles from slipping
As the holes are filled, the bristles which project above the block section, as
shown in Figure 7, are gently beaten down with the fingers until their lower ends
are made about even on the flat surface underneath the half shell.
The Figure (7) last referred to shows the position of the half shell, the lower
section of the block, and of the bristles at the completion of the stage of the process
just described; the upper ends of the bristles in each tuft being uneven, as it is
desirable they should be in the finished brush. At this point the half shell with
the lower section of the block upon it, and the bristles tufted in, as above set forth,
is lifted by the operator from the table or flat surface far enough to permit the
bristles while the shell is held horizontal to be gently further beaten down with
the fingers, or with the palm, until the upper ends of the bristles are about even
with the plane of the upper surface of the block section, and within the chamfered
holes in this upper surface, the lower ends of the bristles now protruding below the
flange of the half shell. In this further beating down the bristles will be made
about even on their upper ends, the uneveness being transferred to their lower ends.
This stage of the process is shown in Figure 8, which is a section similar to that
shown in Figure 7. Still holding the half shell (with the block section and the
bristles in the positions shown in Figure 8) horizontal, the operator now places
the upper section of the tufting block upon the lower section, as shown in Figure 9,
the chamfered holes in the two sections of the tufting block being brought into

page_text: coincidence, as shown in Figures 6 and 9, and the upper ends of the tufts or
bristles-in the lower section being directly under the chamfered holes in the lower
surface of the upper section. The operator, now holding the two sections of the
block and the half shell together turns them over, and places them with the upper
surface of the upper section of the block downwards upon the table; or he may first
lay the upper section of the block upon the table with its chamfered surface upper-
most, and turn over the lower section upon the upper section, carefully keeping the
sections, the half shell, and the bristles, from being displaced. The two sections of
the block being brought together, he now beats with a flat paddle upon the ends of
the tufts of bristles protruding through the concave surface of the half shell, forcing
the lower ends of the bristles gradually into the holes in the lower surface of the
upper section of the block (the chamfering of which holes facilitates the entrance of
the tufts) until the protruding upper ends of the tufts of bristles are about level
with the plane of the flange around the concave side of the half shell, as seen in
Figure 10, which is a longitudinal section through the tufting block, the half shell,
and the tufts of bristles, at the completion of this stage of the process, the lower
ends of the bristles in each tuft as they now rest in the upper section of the block
being as uneven as they need be in the finished brush to secure "penetration,"
while the upper ends are about even.
As is seen in the Drawings, the bristles are up to this point held in place by the
pinch afforded by the holes in the half shell and in the block.
:
The next stage of the process consists in transferring the block, the bristles, and
the half shell, without disturbing their relations, as is shewn in Figure 10, to a
table, upon which they are placed in the same position, and where the even
protruding ends of the tufts of bristles are bent or matted down upon the half shell
with a hot iron by an operator, who carefully turns these ends away from the flange
or wall around the half shell until these ends of the bristles are permanently
flattened, and matted or felted together, and lie within the concavity and below
the plane of the flange or wall of the half shell, leaving a clear margin all around
between the bristles and the walls of the half shell, as shown in Figure 11. The
iron used should not be hot enough to scorch or weaken the bristles, or to melt or
burn the plastic material.
The next stage of the operation consists in taking a wooden core, of shape
conformable to that of the concavity of the half shell, only of so much less size as
will admit of its lying snugly within that concavity without pressing against or
distending the flange in any direction (and for such core poplar wood is found very
suitable by reason of its lightness and compressibility, and its sufficient strength),
and in cementing on one side of this wooden core a thin sheet of celluloid or of
other plastic materials cut to an approximate shape conformable to that of the
wooden core, and not extending into the handle or much beyond the line of the
bristles in that direction, in the instance shown, though it may extend the entire
length of the core if found desirable. This supplemental sheet is designated as the
inside sheet, and to prevent its being displaced in the further progress of the
manufacture it is secured upon the wooden core by the application of ether, alcohol
or a solution of camphor, or by any other liquid solvent or cement of the plastic
material. The wooden core with this inside sheet secured upon it is shown in
Figure 12.
Placing the wooden core (with the inside sheet underneath) upon the matted
bristles, and within the concavity of the half shell as it rests upon the tufting
block, it only remains to cover the wooden core with the other half shell which is
to form the back of the brush, and which corresponds with the first described half
shell before it was perforated (see Figure 1), and we have the parts of the brush
altogether, and all supported in or upon the tufting block, the handle extending
beyond the block, as is seen in Figure 13, which is a longitudinal section through
these parts at this stage of the process, when they are ready to be placed altogether
in the finishing die, taking care not to disturb their positions or to displace the
bristles.

page_text: It is better in practice to place the tufting block and the perforated shell with
the bristles matted down in the die before laying the wooden core with the inside
sheet upon the bristles in the perforated half shell, and before putting on the upper
half shell or top piece.
Figure 14 of the Drawings is a longitudinal section through the packed finishing
die showing the tufting block with its upper section face downwards, resting on the
bottom plate a of the die.
The tufts of bristles are shown matted or ironed down within the concave of the
perforated half shell, which perforated shell rests with its bead b upon the cutting
edge c in the die block; the superimposed inside sheet of the plastic material is
shown resting upon the matted ends of the bristles; the wooden core is in place,
extending the entire length of the interior of the concaved shell, and the half shell,
which is to form the back of the brush, is seen fitting over the wooden core.
The ends of the half shell on top and of the perforated half shell coincide, as
shewn, with each other, and the same relative position is established between the
upright flange or wall of the perforated half shell, and the depending flange of the
other half shell or top piece.
The projecting fins f and beads b around the edges of both the half shells are also
shown in this figure, and over all is placed the top plate d of the finishing die.
This top plate is countersunk in the usual manner of the upper half of a die, and
has plain surfaces, though the surfaces may be ornamented as desired.
It is preferred, however, to make the brush back perfectly plain in order to get a
better finish, and to afterwards attach such medallions, figures, beadings, or other
ornamentation as may be desired. Such ornaments can be moulded separately in
the well-known ways, and then cemented upon the finished brush back or handle,
or upon both, by the application of alcohol, ether, or other solvent, or cement, as is
well understood.
A plan of the top plate is shown in Figure 15. This top plate d of the finishing
die is provided with a groove e or recess, or with a bevel to admit of the escape of
the surplus material, and also has a cutting edge c coinciding with the cutting edge
c in the die block, and with the desired edge of the finished brush (as is shown in
Figure 14).
To ensure a thorough welding together of the flanges of the two half shells the
surfaces of these flanges are softened with ether, alcohol, or other solvent before the
upper half shell is finally put in place in the die, and the die thus packed with the
top plate in position is now placed in a press in which heat also is applied, and an
initial pressure comparatively slight brought down upon the die, so that the beads
bare caught and held between the cutting edges c, c. Under this incipient pressure
the die which is not yet entirely closed is left for a short time, or until it has
become heated sufficiently to soften the plastic material. As this heating and
softening continues the initial pressure is gradually supplemented until the top plate
has been forced entirely down upon the die block, the surplus material being severed
between the cutting edge c of the top plate and the corresponding cutting edge c
around the die block, of which die block Figure 16 is a plan.
The material thus thrown off by the cutting edges is forced into the groove e in
the top plate d, Figures 14 and 15. This die block is a heavy piece of metal
divided transversely as at 1, 1, Figure 16, and provided at each of its corners with
dowel pins g (or other mitering devices) fitting into the corresponding holes h in
the top plate, Figure 15, and in the bottom plate a, Figures 14 and 16. The die
block and top plate are provided with perforations i, i, for the escape of air.
By
thus dividing the die block the tufting block and tufted half shell can be placed in
the die without disturbing or deranging those parts.
The die block is recessed so as to receive and hold snugly the tufting block with
the outline of which the outline of this recess k, Figure 16, corresponds (as seen in
Figure 14), and this recess is of such depth that when the tufting block is in place
its surface next to the perforated half shell will be below the plane of the top of
the die block, and far enough below this plane to admit of a groove / being

page_text: provided around the recess k, in which groove the perforated half shell will first lie,
as seen in Figure 14, and in which it will ultimately be shaped and outlined. The
longer section of the die block has an extension of this groove / to receive and form
the handle of the brush.
The groove around the die block is so formed as to give a cutting edge c
coinciding with the cutting edge c in the top plate as already described, and
between these cutting edges the beads and pins will be severed from the body of
the half shells. As soon as the top plate has been brought down upon the die
block and the die thus entirely closed the process is completed, and it only remains
to shut off the heat, cool the die while still under pressure, and when cooled remove
it from the press. The upper section of the tufting block is then carefully lifted
off from the bristles, and the lower section next carefully removed. The edge of
the brush is then trimmed, its surfaces polished, and if desired it is ornamented as
already described. As the result of this process, a seamless, jointless brush is
obtained with a homogeneous body of material, reinforced by a wooden core, and in
which the bristles are held without threads or wires more uniformly, more securely,
and more permanently than heretofore, the inside sheet being moulded upon the
matted ends of the bristles (so as practically to hold each bristle independently)
and also having filled up the margin between the bristles and the walls of the
perforated half shell, and having become united with the walls of the perforated
half shell so that it prevents any access of moisture to the wooden core, thus
ensuring it against swelling, and the two shells are not only compressed and
condensed, but thoroughly welded together entirely around the peripheries of the
back and handle, and the perforations in the face of the brush are closed about
the tufts of bristles so as to exclude moisture and to ensure a firm support to
each tuft.
Figure 17 is a longitudinal section through the finished brush showing the
transitions occuring in the moulding stages of the improved process from the
conditions and relations of the same parts, as shown in Figure 14.
A celluloid suited to this manufacture may be made as follows:-Prepare
pyroxyline by grinding it in water to a fine pulp in a machine, such as is used in
grinding paper pulp; strain off the water as far as practicable, and then subject
this pulp to powerful pressure; for example, in a perforated vessel to further expel
the aqueous moisture and to bring it to a comparatively solid and dry state, yet
still retaining sufficient moisture to prevent it from burning in the further stages of
the process. Comminute gum camphor by grinding it in water, or preferably by
pounding or rolling it, and thoroughly incorporate with the pyroxyline pulp in the
condition last above described this finely comminuted camphor, in about the pro-
portion of one part by weight of camphor to two parts by weight of the pyroxyline
in the pulp. These proportions may however be somewhat varied with good results.
With the camphor, also thoroughly incorporate with the pulp, any pigments,
colouring matter, or other materials that may be adapted to the requirements of the
articles into which the product is to be manufactured. The camphor or camphor
and other ingredients having been thus thoroughly mixed with the pulp, next
subject the mass to a powerful pressure in order to expel the remaining aqueous
moisture, and thereby not only dry the mixture, but force the camphor into more
intimate contact with the pyroxyline throughout the mass. The dried and com-
pressed mass is next placed in a suitable mould or vessel open at the top, and into
this open top is fitted a platen or plunger. The vessel is then placed in a hydraulic
or other powerful press, and a heavy pressure applied to the platen or plunger is
brought to bear upon the mixture, which, while thus under pressure, is heated up
by steam or other convenient means to a temperature of from 150° to 300°
Fahrenheit, varying according to the quantity of the mixture, and the mixture is
kept at this temperature and under this pressure until the converting power of the
camphor shall have been exerted upon the pyroxyline throughout the mass. The
process of transformation is rapidly effected, and is completed almost as soon as the

page_text: mass attains its maximum temperature, the resulting product being a homogeneous
product. This product as it comes from the press is of a consistency resembling
that of sole leather, but upon exposure to the atmosphere it hardens by reason of a
slight evaporation of the camphor. The ultimate product includes however a large
proportion of the camphor as a permanent accretion to the mass.
I am not aware that prior to the above specified Invention a brush had ever been
made by shaping a plastic material into what I have shown and described as a half
shell, or that such a half shell had ever been perforated, or the bristles tufted
directly into a perforated half shell, or so tufted in and matted down upon one side
of the half shell, or a tufted half shell subjected to the process herein-before set
forth.
Neither am I aware of any prior process by which a wooden core could be
enclosed in a brush the body of which was composed of a plastic material, and a
diaphragm of the material interposed between the wooden core and the inner ends
of the bristles, as is done in the improved process.
I also believe the above-described sectional tufting block for tufting the bristles
in the half shell to be novel; and in short the entire process herein-before set forth
I believe to be new, and only practicable in connection with a material (such as
celluloid) which, while plastic under heat, is hard enough at ordinary temperatures
to admit of the manipulations described.
Therefore having thus set forth the nature and objects of the improvements,
what I claim herein as new and desire to secure by Letters Patent is, in the manu-
facture of brushes,-
First. As a new article of manufacture, the half shell of plastic material for
brushes, substantially as herein-before described and shown in Figures 1 and 2 of
the accompanying Drawings.
Second. As a new article of manufacture, the perforated half shell of plastic
material for brushes, substantially as herein-before described and shown in Figure 3
of the accompanying Drawings.
Third. A tufting block composed of horizontal sections with holes extending
through the sections and chamfered at the middle part of the block, substantially
as described and as shown in Figures 4, 5, and 6 of the accompanying Drawings for
the purposes set forth.
Fourth. The combination of the perforated half shell and the sectional tufting
block, substantially as and for the purposes described.
Fifth. The process, substantially as herein described, of tufting the bristles into a
perforated half shell and into a tufting block divided into horizontal sections, as
shown in Figures 7, 8, 9, and 10 of the accompanying Drawings.
Sixth. The method, substantially as herein described, of securing the inner ends
of the tufted bristles by ironing or matting them down upon the inside of the half
shell, as shown in Figure 11 of the accompanying Drawings.
Seventh. The combination with the wooden core of an inside sheet of plastic
material, substantially as and for the purposes described, and as shown in Figure 12
of the accompanying Drawings.
Eighth. The combination of the perforated half shell, the matted ends of the
bristles, the wooden core, and the inside sheet interposed between the bristles and
the core, for the purposes described and substantially as shown in Figures 13 and 14
of the accompanying Drawings.
Ninth. The combination of a tufting block, tufts of bristles with matted inner
ends, a perforated half shell, a wooden core, an interposed sheet of plastic material
between the bristles and the core, and a half shell for the back of the brush, sub-
stantially as and for the purposes described, and as shown in Figure 14 of the
accompanying Drawings.
Tenth. The process of forming a half shell, perforating the shell, tufting the
bristles in the shell and in the tufting block, matting the inner ends of the bristles
upon the inside of the shell, interposing an inside sheet of plastic material, super-

page_text: imposing a wooden core, covering the wooden core with a half shell of plastic
material, and uniting these parts under heat and pressure, substantially as and for
the purposes described.
Eleventh. As a new article of manufacture, a brush, the body of which is
composed of a plastic material, enclosing a wooden core, the bristles being supported
and secured entirely in plastic material, the plastic material being interposed
between the bristles and the wooden core, substantially as and for the purposes
described, and as shown in Figure 17 of the accompanying Drawings.
Twelfth. The process, substantially as herein described, of moulding the half
shells, tufting the bristles in the perforated shell, and uniting the two half shells in
a die under heat and pressure.
Thirteenth. The combination in a die of a top plate, a bottom plate, and a trans-
versely divided die block, all of these parts being separable, substantially as and
for the purposes described, and as shown in Figures 14, 15, and 16 of the
accompanying Drawings.
Fourteenth. The combination of a transversely-divided die block and a sectional
tufting block, substantially as and for the purposes described.
In witness whereof, I, the said Sydney Pitt, have hereunto set my hand
and seal, this Fifth day of October, in the year of our Lord One thousand
eight hundred and seventy-seven.
SYDNEY PITT. (1.8.)