IMPROVEMENTS IN THE CASTING OF METALS AND IN APPARATUS THEREFOR
Year: 1875

page_text: LETTERS PATENT to George Haseltine, of the "International Patent
Office," Southampton Buildings, London, Doctor of Laws, for the
Invention of "IMPROVEMENTS IN THE CASTING OF METALS AND IN
APPARATUS THEREFOR."-A communication from abroad by Charles
Grasser, of Somerville, Massachusetts, United States of America,
Metal Founder.
Sealed the 4th January 1876, and dated the 8th July 1875.
PROVISIONAL SPECIFICATION left by the said George Haseltine at the
Office of the Commissioners of Patents, with his Petition, on the
8th July 1875.
I, GEORGE HASELTINE, of the "International Patent Office," South-
ampton Buildings, London, Doctor of Laws, do hereby declare the
nature of the said Invention for "IMPROVEMENTS IN THE CASTING OF
METALS AND IN APPARATUS THEREFOR," a communication, to be as
follows:-
-
The object of this Invention is to produce a casting in metal from a
given pattern, which casting will be a perfect copy of such pattern,
without requiring much, if any, after finishing or chiselling work. To
A

page_text: accomplish this object it is necessary in the first place to produce a
mould or matrix of the pattern or object to be cast as nearly perfect as
is possible with material suitable for the purpose.
The said Invention relates partly to a method of making patterns of
wax, resin, paraffine, or similar material which will melt at a moderate
temperature, or of a composition of such materials, the process of
making such patterns being so rapid and easy as to avoid the necessity
of drawing the patterns. To produce such patterns of wax or similar
material they are cast within pattern moulds or matrices of gum.
elastic, which pattern moulds are first formed on an original model, and
removed therefrom by slitting and stretching. The wax patterns are
removed from the matrices in the same way, and are then used for
forming the permanent clay moulds. This mode of making wax or
similar patterns is so rapid and easy as to avoid the necessity of drawing
them from the permanent moulds, but permits them to be melted
and run from the moulds when done with, and any remainder of
such pattern material is consumed in the process of baking the
moulds.
The said Invention is not restricted to any shape or form of pattern.
It avoids the slow and laborious process of making false corcs if
the object to be cast is of such a shape as to necessitate the
forming of the mould in several pieces, as in the case of a statue or
statuctte.
In order to produce a mould sufficiently porous to permit the escape
of the gases generated together with the air in the mould, and to permit
the metal to lic closely to the surface of the mould after pouring it, it
has been customary in casting refractory metals to employ for the
material of the moulds a coarse loam or sand, and pack it somewhat
loosely within the flask.
One object of the present Invention is to permit the use of a
compact and fine loam for the moulds, and of a very fine facing
material to produce the surface or portion of the metal which comes in
direct contact with the pattern.
The said Invention also relates partly to a mode of forming moulds
for casting metal by the application to the patterns of a fine slush of
fine clay, and coating this with a mantle of less wet and more plastic
clay, the surplus moisture being taken up in each case by the appli-

page_text: cation of brickdust or other absorbent material, and the mould being
pressed on the pattern by enclosing it in an elastic and impervious bag
and applying to the exterior thereof a moderate pressure of air, water,
or other fluid within a tight receiver. The fusible pattern is afterwards
run from the mould, and the latter is dried and baked.
It will bo manifest to those skilled in the art that the use of a dense
material for moulds necessitates the adoption of some mode of intro-
ducing a metal other than the simple mode of pouring it from a pot or
ladle.
And the said Invention relates partly to a simple expedient for intro-
ducing the molten metal under sufficient pressure. A furnace of
peculiar construction is employed in connection with an clevated pot or
crucible, from which the molten metal descends through a stand pipe
constructed of tubular sections coupled together, and with radial flanges
for the purpose of fixing the stand pipe concentrically within the
vertical furnace and with a T shaped lower extremity to provide for the
discharge of the metal, the vertical height of the column of molten
metal determining the pressure at which it is introduced.
The flow of the metal is controlled by a valve forming a permanent
part of the apparatus constructed of or encased with a compound
porcelain and blacklead, crucible stuff, or analagous material, which is
adapted to bear the necessary high temperaturo and also to receive
accurate fitting and to work freely under unequal temperatures. The
said valve works within a mouth-piece, also of porcelain and blacklead
composition, formed with a projecting nozzle to deliver the metal to
the mould.
The mould and flask are supported on a table, adjustable vertically
to bring the mould gate in proper juxtaposition with the mouth-piece of
the furnace.
Other parts of the apparatus which require accurate fitting, and to
resist a high temperature, are likewise made of blacklead, crucible
stuff, and porcelain, or equivalent material.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent,
filed by the said George Haseltine in the Great Seal Patent Office
on the 8th January 1876.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, GEORGE
HASELTINE, of the "International Patent Office," Southampton Build-
ings, London, Doctor of Laws, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her
Letters Patent, bearing date the Eighth day of July, in the year
of our Lord One thousand eight hundred and seventy-five, in the thirty-
ninth year of Her reign, did, for Herself, Her heirs and successors,
give and grant unto me, the said George Haseltine, Her special licence
that I, the said George Haseltine, my executors, administrators, and
assigns, or such others as I, the said George Haseltine, 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
CASTING OF METALS, AND IN APPARATUS THEREFOR," a communication to me
from abroad by Charles Grasser, of Sommerville, Massachusetts, United
States of America, Metal Founder, upon the condition (amongst
others) that I, the said George Haseltine, my executors or adminis-
trators, by an instrument in writing under my, 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, the said George Haseltine, do hereby declare
the nature of the said Invention, and in what manner the same is to be
performed, to be particularly described and ascertained in and by the
following statement, reference being had to the accompanying Drawing
forming a part of this Specification:-
The main object of this Invention is to produce a casting in metal
from a given pattern, which casting will be a perfect copy of such
pattern without requiring much, if any, after finishing or chiselling

page_text: work. To accomplish this object it is necessary in the first place to
produce a mould or matrix of the pattern or article to be cast as nearly
perfect as is possible with material suitable for the purpose.
The said Invention consists in part in a method of making patterns of
wax, resin, paraffine, or such like material which will melt at a moderate
temperature, or of a composition of such materials, the process of
making such patterns being so rapid and easy as to avoid the necessity
of drawing the patterns. To produce such patterns of wax or similar
material they are cast within pattern moulds or matrices of gum elastic,
which pattern moulds are first formed on an original model and removed
therefrom by slitting and stretching. The wax patterns are removed
from the matrices in the same way and are then used for forming the
permanent clay moulds. This mode of making wax or similar patterns
is so rapid and easy as to avoid the necessity of drawing them from the
permanent moulds, but permits them to be melted and run from the
moulds when done with, and any remainder of such pattern material is
consumed in the process of baking the moulds.
The said Invention is not restricted to any shape or form of pattern.
It avoids the slow and laborious process of making false cores if the
object to be east be of such a shape as to necessitate the forming of the
mould in several pieces, as in the case of a figure or statuette.
In order to produce a mould sufficiently porous to permit the escape
of the gases generated, together with the air in the mould, and to
permit the metal to lie closely to the surface of the mould after pouring,
it has been customary in casting refractory metals to employ for the
material of the moulds a coarse loam or sand and to pack it somewhat
loosely within the flask.
One object of the present Invention is to permit the use of a more
compact and fine loam for the moulds, and of a very fine facing material
to produce the surface or portion of the metal which comes in direct
contact with the pattern.
The said Invention consists partly in a mode of forming moulds for
casting metal by the application to the patterns of a fine slush of fine
clay, and coating this with a mantle of less wet and more plastic clay,
the surplus moisture being taken up in each case by the application
of brick dust or other absorbent material, and the mould being pressed

page_text: on the pattern by enclosing it in an elastic and impervious bag, and
applying to the exterior thereof a moderate pressure of air, water, or
other fluid within a tight receiver. The fusible pattern is afterwards
run from the mould, and the latter is dried and baked.
It will be manifest to those skilled in the art that the use of a dense
material for moulds necessitates the adoption of some modo of intro-
ducing a metal other than the simple mode of pouring it from a pot
or ladle.
The present Invention consists in part in a simple expedient for
introducing the molten metal under sufficient pressure. A furnace
of peculiar construction is employed in connection with an elevated
pot or crucible from which the molten metal descends through a stand
pipe constructed of tubular sections, coupled together and with radial
flanges for the purpose of fixing the stand pipe concentrically within
the vertical furnace, and with a T shaped lower extremity to provide
for the discharge of the metal, the vertical height of the column of
'molten metal determining the pressure at which it is introduced.
The flow of the metal is controlled by a valve forming a permanent
part of the apparatus constructed of or encased with a compound of
porcelain and black lead, crucible stuff or analogous material which is
adapted to bear the necessary high temperature, and also to receive
accurate fitting, and to work freely under unequal temperatures. The
said valve works within a mouth-piece, also of porcelain and black lead
composition formed with a projecting nozzle to deliver the metal to
the mould.
Tho mould and flask are supported on a table adjustable vertically
to bring the mould gato in proper juxtaposition with the mouth-picce
of the furnace.
Other parts of the apparatus which require accurate fitting and to
resist a high temperature are likewise made of black lead, crucible stuff,
and porcelain, or equivalent material.
The furnace is heated by means of air and gas introduced from
separate reservoirs through separate pipes, or it may be heated by
solid fuel.
My method of forming elastic moulds for producing wax patterns
is as follows:-The elastic moulds are made of good and clastic vul-

page_text: canized india-rubber in the following manner:-India-rubber cannot be
vulcanized on every material. If the original pattern or model on
which the pattern mould is to be formed be made of any metal which
will be acted on by sulphur or sulphurous gases, such original pattern
or model must be covered with a deposit of lead or iron, plaster of Paris,
parian marble, and all other mineral substances which may be used
for making a model are suitable.
If metal is used for making the model iron, type metal, or lead will
be preferable. All other metals or compositions must be covered by the
electro process with lead or iron.
Such first or original model or pattern from which an elastic mould
is to be made ought to be prepared with the greatest care and perfection,
as on this first model depends all the perfection and sharpness of every
duplicate cast thereafter.
When the first original model is procured the operator takes a
solution (properly mixed) of india-rubber in benzine, and with a brush
applies over the model or pattern a thin coat of such solution, which
soon dries and forms a sticky or pasty surface adapted for the ready
adhesion of the vulcanized rubber, which previously is rolled out in
thin sheets about ½ of an inch thick. The first layer of rubber
must be laid on very carefully, and every corner or recess in the model
must be well filled by small bits of rubber, being carefully forced in
with a small stick, care being taken to avoid the confinement of air
in any of the recesses. On all smooth or comparatively even parts of
the model the rubber may be laid on in larger picces, but every pieco
laid on must be firmly pressed on and made to adhere to the model.
The first layer or coat of rubber being laid on, all over, and around the
model a second layer is added, and so on until the rubber lies on the
model to a thickness of about a quarter of an inch. Smaller objects
may have a thinner coat, while larger ones require even a much thicker.
coat. What is to be obtained is a thickness of rubber which will retain
its shape after vulcanizing, and bear its own weight without collapsing
the elastic mould.
When a sufficient thickness of rubber is laid around the model in the
manner described the model with the rubber around it is placed into a
rubber vulcanizer (of the construction commonly used for vulcanizing
rubber) under water pressure to the rubber for the purpose of firmly

page_text: pressing the rubber to the mould or object from which it is to obtain an
impression during the process of vulcanizing. Such an apparatus or
vulcanizer consists of a strong inner vessel with a closable opening for
the introduction of the object to be vulcanized. This inside vessel is
surrounded by another strong vessel or steam jacket and connected with
a force pnmp operated outside. The inside vessel contains water for
applying high pressure on the rubber by means of the force pump. The
outside vessel or jacket contains steam of the required temperature to
vulcanize the rubber.
The model must be entirely surrounded by the rubber to prevent the
forcing of the water (under a pressure of 100 pounds to the square inch)
between the rubber and model which would prevent the rubber from
taking a perfect and sharp impression of the model. When the rubber
is well vulcanized it is taken from the vulcanizer, and with a sharp
knife the rubber is cut in such a way as to permit the removal of the
model. It is not necessary to cut the rubber into halves or pieces,
because by its clasticity it may, when simply slit, be pulled apart
sufficiently to release the model. On removing the model an clastic
mould of the object is obtained, and if properly made the mould
possesses all the perfection of the original model. In this elastic mould
an opening is cut at the proper place for the introduction of melted
wax, resin, or paraffine, or a compound of these or other analogous
material.
Before the wax is poured into the mould for the purpose of forming a
wax pattern the edges of the cut are coated with a thin solution of
vulcanized rubber in benzine, which in a few minutes will be very
adhesive, and the cut edges may be so joined (if done with care) as not
to leave a trace of a joint. Then the rubber mould is suspended in cold
water for the purpose of cooling the wax and retaining the rubber mould
in shape. Then the melted wax is poured slowly into the rubber mould a
at the opening cut for that purpose until full. If the object is of such
a nature as to be hollow when cast in metal the surplus wax is poured
out as soon as the wax has formed a shell by cooling on the sides first.
When the wax has fully cooled in the rubber mould, which cooling takes
place in a few minutes, according to the temperature the mould is 3
removed from the water, and at the place where the joint is in the
rubber mould the said mould is easily torn apart, and may be readily
removed from the wax pattern without injuring the finest parts thereof.

page_text: If the elastic or rubber mould is perfect it will be found that the wax
pattern so produced is a perfect facsimile of the same.
Such a
rubber mould can be used without injury for casting thousands of wax
patterns.
It will be easily understood by those familiar with the art of making
undercut work in metal that such an elastic mould for casting wax
patterns if made of good rubber is almost without limitation in its
applicability to intricately undercut work, whether it be a statuette or
other metal work.
The second part of this Invention relates to the forming of a loam
mould around a pattern of wax, resin, or paraffine cast in the elastic
mould.
This object is effected in the following manner:-A fine slush of clay
or loam is prepared suitable for making loam moulds for casting metals.
This slush or paste of clay is applied to the wax pattern with a brush to
the thickness of about 1/8" of an inch, care being taken to introduce the
clay slush into every recess of the pattern. Then the same is covered
with a body of finely-ground brick or other burned clay. The well-
known capacity of burnt clay for absorbing moisture is taken advantage
of in this novel manner to quickly absorb the surplus water in the clay
slush with which the wax pattern is covered. In a few minutes after
covering the slushed pattern it may be taken from under the brickdust,
and whatever brickdust clings to the same may readily be removed by a
soft brush. It will then be found that the brickdust has absorbed most
of the water and the slush has been transformed into a nearly dry
mantle or coat of clay lying firmly and closely on the pattern. As this
first thin layer of clay would be of insufficient strength to answer as a
mould another mantle or coat of coarser loam in a plastic state and
mixed with fibrous material, such as is commonly used with clay to
afford greater strength, is laid on the first fine coat, and is pressed or
daubed on by hand to the thickness of about one inch, more or less,
according to the size of the mould, and then the whole is buried in brick-
dust to absorb the water and dry it as above stated.
The emplotment of an absorbent material as above described enables
'

page_text: The absorbent material in promptly and readily drying the slush has
two important and practical effects,―
First. It prevents any falling away of the material of the mould from
any part of the pattern, which is liable to occur in the comparatively
slow process of drying by evaporation. This difficulty renders it
impossible under the ordinary process of constructing the moulds to
employ the slush in so wet a state as to adapt it to enter the fine inter-
stices of the pattern as closely and completely as it can under the process
described above.
Second. The rapid drying of the material of the mould causes a
shrinkage therein, which has the effect of pressing the partly dry but
still plastic material still more firmly and securely upon the pattern, and
into all its recesses. This effect is produced more especially in the rapid
drying of the entire substance of the mould after the application of the
outer coat or mantle.
Although a very fine and perfect mould is obtained when made in
the manner described, it is still preferred to employ another auxiliary to
produce the best results with almost unfailing certainty. By means of
a very simple apparatus the operator can apply, in addition to the
shrinkage of the material, a uniform moderate pressure, which is
applied to the plastic mould material in such a manner as to press
equally on every part of the pattern, no matter of what shape it may be.
This apparatus consists of a simple screw press provided with a movable
air-tight base and extended platform.
Figures 1 and 2 in the Drawing represent vertical sections of this
press apparatus. The air-tight base A is provided on top with a cover B,
which is fastened to the screw C, so as to close or open the baso A for
the purpose of introducing the mould and confining the compressed air,
which is employed as the pressure medium. The base rests and runs on
two V slides D, so that it may readily be removed from under the cover.
As soon as the second or outer coat of the mould or mantle is applied to
the pattern the operator introduces the whole into an elastic bag E of
thin rubber within the box A, fills the said bag around the mould with
the capillary or absorbent material or brickdust, securely binding the
open end of the bag, pushes the base under the screw cover, closes the
cover by means of screw O, and admits through the pipe F a current of
compressed air at a pressure of about 12 or 15 pounds to the square
'

page_text: inch. The air, being prevented by the rubber bag from coming in con-
tact with the soft mould material, will exercise a very uniform pressure
on the outside of the bag, and through that on the brickdust and plastic
material, thereby pressing it still more to the pattern, and assisting the
brickdust to absorb the water. But a few minutes are required when
the air is released by raising the cover B. When the bag is removed
from the base the mould may be taken out, and the adhering brickdust
is easily brushed away. The mould still containing some moisture is now
set aside to dry completely by evaporation, previous to which a proper
opening has to be cut for the introduction of the metal. When a
number of such moulds are ready, and nearly dry, they are placed into a
moderately heated oven to gradually melt out the wax, resin, paraffin, or
composition pattern, if the same has been used. The wax may be nearly
all gathered in a dripping pan set in the oven.
gradually raised until the mould is at a low red heat, so as to burn out
all the wax, and render the mould strong and hard, and ready for
casting.
This done the heat is
When an object is to be cast hollow the wax pattern is cast hollow, as
above described, and is filled in with a composition of one part of coarse
ground brick, one part of plaster of Paris, and one part of sandy clay
or loam.
The composition is mixed like plaster, so that it may be
poured into the hollow part of the pattern. It will set like plaster,
and proper core or stay rods will hold it like any other core in the proper
position after the wax is melted out.
Although this new method of moulding is specially adapted for and
effects the greatest saving of labor in connection with irregular shaped,
round, or under-cut castings, it may also be used for flat or straight
castings, and in such cases metal patterns may be used, which are treated
in the moulding process in the same manner, only that the mould is
to be made in two halves, and the pattern is drawn out before the
moulding loam becomes too dry, that is, after it is taken out of the
brickdust. When a wax or resin pattern is used the mould is made
throughout of one piece.
The third part of this Invention relates to the casting of the object
moulded, and the apparatus to be employed therein.
Every practical metal founder is aware that if a mould is made of too
fine and dense material, the metal cannot be made to lic closely to the

page_text: mould and produce a perfect casting of the same, unless some means for
introducing the metal be employed other than simply pouring it into
the mould from the melting pot, as in the usual mode of casting.
As a very fine facing slush is employed in this improved process to
obtain a perfectly fine face in the mould, a very close and fine porous
surface is produced which requires more than the pressure or weight of a
short gate or riser (as now used on castings), if the metal is to lic to
the dense mould and produce a sharp and well defined casting. To
accomplish this object an apparatus or furnace is employed, which is so
constructed as to give a pressure of about 20 pounds to the square inch
on the fluid metal, and of such a construction as to form a fountain or
reservoir from which the melted metal may be introduced in quantitics
accurately apportioned to fill any mould no matter what the quantity
required, be it one ounce or the whole contents of the furnace. This
apparatus consists of a melting pot arranged and resting on a stand pipe
of about six feet in height. Said pot has a hole in the bottom and is
connected with the stand pipe.
At the lower end of the stand pipe is a T shaped end which helps to
support the pot and pipe, said T shaped end has an outlet which is
provided with a valve or faucet-like closable mouth-piece, and is arranged
to admit the fluid metal from the pot through the stand pipe into the
mould, at a pressure of about 20 pounds to the square inch. By the
arrangement or provision of a valve or faucet, the flow of the metal may
be cut off or let into the mould at pleasure. The whole pot, stand pipo,
and valve or faucet aro all firmly connected and enclosed in a furnace of
corresponding height and size, for the purpose of heating the metal to
fusion and form permanent parts of the furnace.
In the Drawing three different modifications of my furnace are
represented, two of which are of such construction as to produce the
required heat to fuse the metal by the burning of gas and air.
Figure 5 represents an clevation of a furnace with the iron front,
fire-brick lining, and table removed, so as to show the interior of the
furnace which may be heated by wood, coke, or charcoal.
samc.
In all modifications represented the essential principle remains the
The apparatus or furnace is also provided with an adjustable &
table on which the moulds are fastened by means of a clamp and are
then ready to be filled with molten metal.

page_text: Figure 4 represents a front elevation of the same furnace with the
front iron casing, fire-brick lining, and mould table removed so as to
show the interior of the furnace.
Figure 6 represents a cross section of Figure 3 on line A, A; Figure 7
represents a back view of the adjustable table; Figure 8 is a cross
section of Figure 4 on line B, B.
Similar figures denote corresponding parts of the apparatus.
The construction of the furnace or apparatus is as follows:-An iron
casing, is composed of different sections and pieces until the required
height is obtained; said iron casing is firmly screwed together by the
several different flanges 2 provided for that purpose. The whole rests
on a platform 3; this iron casing is for the purpose of firmly holding
together the several pieces of the fire-brick lining 4. The melting pot 5
is made out of the best quality of black lead crucible material, and is
provided with a hole 6 and an extension 7 of the same size as the stand
pipe, so as to make a good connection with the same.
The stand pipe 8 is made in several sections and of the same material
as the pot, and is provided with extending flanges 9, plainly shown in
Figure 8, said flanges run down on both sides of the pipe and are some-
what notched in the front and back of the fire-brick lining, as may be
seen by Figure 8, and are for the purpose of forming a partition and
dividing the furnace into two parts or flues for a uniform circulation of
the heat. Furthermore, said flanges give a firmness and support to
the stand pipes. The several sections of the stand pipe are well and
firmly jointed together by another smaller pipe 10 fitted and pushed in
the outside larger pipe covering the joints of the larger pipe and making
a connection with the melting pot. The stand pipe 8 ends near the
bottom of the furnace in a cross piece 11, and extends partly into a
hole in the back wall of the furnace; at the front end of this cross pieco
there is a mouth-piece 12 which forms part of the valve or faucet and
extends through the fire-brick front wall fitting into a proper seat on
the iron casing; the mouth-picce or faucet ends in a half globe-shaped
lip 13 projecting through the front iron casing, and is for the purpose
of making the connection with the mould to be filled with metal; the
mouth-piece is closed at one side and has a taper-shaped opening on the
other for the admission of the plug 14, which plug forms the inter-
cepting medium to cut off or permit the flow of the meial; this plug 14

page_text: has a stem or extension passing through the fire-brick lining to the
outside of the furnace where it is provided with a lever or wrench 15 by
means of which the plug may be turned to cut off or admit the metal;
the mouth-piece 12 has an opening 16 at its lower side, said opening
making connection with the pipe 17 extending to the outside of the
furnace, said opening and pipe are for the purpose of giving an outlet
to the metal which is left in duct 18, crossing the plug when it is turned
to cut off the supply of the metal; the metal remaining in the duct
finds an outlet through the pipe 17, so that the duct may be empty for
a free passage of the fluid metal when the succeeding mould is to be
filled.
By means of a set screw 19 pressing against an iron plate 20 the
cross end of the stand pipe and the mouth-piece 12 are pressed against
the front iron casing, making the whole firm and solid.
The heating of the furnace is effected by the burning of gas which
has its inlet from a base 21 through one or two supply pipes 22 at the
bottom of the furnace; the required supply of air comes from the base 24
through a pipe or pipes 25. The gases ignited pass from the bottom of
the furnace in the directions of the arrows shown in Figure 1 to the
top, encircle the melting pot, and pass again down to the bottom of the
furnace, as indicated by the arrows; what is not consumed escapes
through a flue 26.
If the heating of the furnace is to be effected by the burning of wood
or other fuel giving a good flame the shape of the furnace has to be
modified, as may be seen in Figure 5. On one side of the furnace is
an attachment or chamber 27 for the reception and consumption of the
fucl; this chamber is provided at the top with a trap door 28 for the
introduction of the fuel, and at the bottom with grate bars 31. If the
fuel is wood it ought to be in long sticks so as to create a high flame and
stand upright in the combustion chamber. The combustion chamber is
separated from the furnace containing the stand pipe and melting pot
by a partition 29, the said partition being provided with a series of
holes 30 through which the flame passes in the direction of the arrows
around the pot and down to the bottom of the furnace, finding an
escape through the flue 32 in the bottom of the furnace.
Another part of the said Invention relates to the construction of a
mouth-piccc, valve, or faucet, and the material for the same.

page_text: When speaking of a valve or faucet and mouth-piece fitting so nicely
as to prevent the leakage of melted metal at a white heat and high
pressure of 20 lbs. to the square inch, and at the same time to be of
such a nature as to operate freely and be closed and opened at the will
of the operator, and be of some considerable durability and strength, it
must appear to a person of practical knowledge in the handling of
refractory metals in fusion that a material must be employed which has
the property of great hardness and strength combined with great
resistance to high heat, and also capacity to resist the unequal tem-
perature to which such valves or faucet and mouth-piece must
unavoidably be exposed without breaking or shattering the same to
pieces, as most of the materials for resisting great heat and which are
used for metal melting pots, furnace lining, and the like, are of a rather
soft, coarse, and easy crumbling composition, and are so even when
burned under a very high heat, or else if hard when burned will glazo
and break to pieces when exposed to unequal temperature..
To overcome these difficulties is one important object of this Invention,
and the manner of making such valves, pipes, faucets, and mouth-pieces
forms a part of the improvements.
The material employed to make the valve faucet and mouth-piece is a
composition of the material used of the best quality of blacklead
crucibles and the mixture used for the making of the world renowned
"Meissen porcelain," two parts of the said blacklead crucible material
aro well mixed with one part of the porcelain clay. When in a plastic
state the rough outline and form of the piece is given, then when nearly.
dry it may be finished and properly shaped by turning and cutting.
This done all the parts and surfaces of the piece made (be it valve,
faucet, or mouth-piece, or a pipe) which are exposed to wear or friction
from another part working or moving in the other, are laid over or
covered with a thin layer of said composition only composed of different
proportions, namely, two parts porcelain clay, and one part blacklead
mixture, but very finely ground, or even with the pure porcelain clay
alone. Great care must be taken to lay this coating or in uniform
thickness, and not thicker than of an inch. When all nicely
finished in the shape desired the parts so made are rendered perfectly
dry, and afterwards are burnt in a close muffle furnaco or other closed
fire-proof vessel. The heat required to burn such parts must be raised
gradually to a white heat, which must be maintained for three or four

page_text: hours, and they are then slowly cooled off. When burnt as explained it
will be found that the main body of the article so made is much harder
and stronger than if made out of crucible material alone, and that the
surfaces on which the said layer of porcelain is laid in the manner
described is hard and of a flint-like nature so that it may be ground and
polished to a perfect fit with any other part of the valve or faucet.
When two parts are so fitted together they will move and work in each
other even if exposed to a while heat, and with but little if any wear or
friction. If any part so made should shew fine surface cracks of the
porcelain coating after burning, all that is necessary is to fill those fine
cracks again with a fine slush or paste of the same mixture, rubbing it
well into the cracks, and after burning it over again as described it will
be found that all the cracks are closed, leaving a uniform surface.
When the apparatus above described was first put in practical
operation the valves, mouth-piece, and such parts were made of the pure
porcelain clay and encased with a blacklead mixture so as to protect
them against too sudden heat or cooling. But as porcelain cannot be
made very thick or of greatly unequal thickness in different parts
without great risk in fracturing the same it was a most difficult task to
make such parts well, and being thin they were broken too easily when
in use. By adapting the blacklead crucible mixture in combination
with porcelain clay a material is obtained of considerable strength and
bardness which can be made into a piece or article of considerable
size and thickness without being liable to fracture in burning or
use. Furthermore, it will stand as sudden a change of temperaturo
as a blacklead crucible without fracturing.
The essential point of having a hard and smooth surface for grinding
and fitting together the surfaces coming in wearing contact is obtained
by the application of the thin layer or coat of porcelain (or composition
partly of porcelain) which is laid on the surface of the body of the article 3
before burning.
If desired all the different parts of the furnace, such as the pot,
stand pipe, cross end, and the like may be made of the above described
mixture of blacklead, crucible mixture, and porcelain, which would
make the whole much stronger but somewhat more expensive. Further-
more, the said composition of blacklead, crucible mixture, and porcelain
in the proportions stated is a most excellent material, of which all

page_text: kinds of vessels and other things may be made which are or may be of
great utility in the manufacture of metals by reason of the greater
strength and resistance to heat. The said mixture consists of about 4
parts pure Ceylon blacklead, 3 parts of German clay (called in German
Kiesselguhr), 4 parts of pure kaolin, and 1 part of felspar. Slight
variations will not change the quality to any extent.
Having made a number of moulds in the manner described, each
mould is placed in a suitable flask or iron case, which has a concave
semicircular hole on one end, and all the empty space in the flask left by
the mould is closely packed with moist moulding sand, so as to keep the
mould in proper position and prevent its bursting when the metal is let in.
The flask is then provided with a cover 40 laid on the adjustable table 41,
the concave semicircular hole in the flask being towards the mouth-
piece of the furnace, then by means of the screw 42 and hand wheel 43
the table is raised or lowered until the concave semicircular hole in the
flask is in line with the ball-shaped lip or end of the mouth-piece of the
furnace, the flask being fastened to the table by the bolt 44 and
clamp 45; the table, swinging on its axis 46, being swung towards the
furnace by means of the lever 47, will make a close connection of the
mould with the mouth-piece, through which the fluid metal will enter
the mould as soon as the valve is opened by means of the lover 48.
The pressure of the metal is equal to the weight produced by the height
of the column of fluid metal in the stand pipe.
The above described casting apparatus is also an excellent machine
for making castings out of the softer and easy melting metals and
compositions by reason of the great and uniform nicoty with which the
pressure can be regulated by the height of the stand pipe, of the easy
and economical operation of the same. The pressure of the metal once
regulated by the height of the stand pipe is always the same, and for
that reason plaster moulds may be employed for metals melting at a low
degree of heat.
The great advantage of the apparatus when employed for casting
stereotype plates could be only appreciated when seen in operation for
that purpose.
If the said apparatus is used for casting metals which melt at a low
heat the pot, stand pipe, and valve, or faucet may be made of iron, the
shape and principle remaining the same.

page_text: Having thus fully described the said Invention as communicated to
me by my foreign correspondent, and the manner of performing the
same, I wish it understood that I claim,―
First. An elastic india-rubber mould for forming of wax, paraffine,
resin, or other suitable material which will melt at a moderate tempe-
rature, patterns to be used in the art of making moulds for casting, or
otherwise filling such moulds with metal.
Second. The process of constructing moulds for casting metals by the
application to the patterns of the inner material of the mould in a soft
and wet state, drying the same by an absorbent material, and subse-
quently applying the more dry and plastic coat or mantle, as above set
forth.
Third. The manner of applying a moderate pressure on the exterior of
a mould of irregular shape by enclosing the same in an air or water-
tight bag, and the whole in a closed case or box, as above set forth.
Fourth. A furnace in combination with a fixed metal pot elevated at
a required height on a stand pipe to obtain a high column of molten
metal, thereby obtaining a uniform and well regulated pressure on the
metal allowed to flow in the mould through the stand pipe and valve, as
above set forth.
Fifth. The combination of a valve or faucet with the stand pipe and
melting pot as a permanent fixture and part of the same, for the purpose
set forth.
Sixth. The mouth-piece in connection with the T shaped end of the
stand pipe, as above described and for the purpose set forth.
Seventh. The combination with a casting furnace of an adjustable
tabie, as above described and for the purpose specified.
Eighth. The flanges on the stand pipe, as above described and for the
purpose set forth.
Ninth. The use of porcelain clay in combination with the black lead
crucible stuff, or its component parts, in the construction of parts of a
furnace, as herein described and for the purpose set forth.
Tenth. The use of porcelain clay, or its component parts, as a facing
or plating to the wearing surfaces of a valve, faucet, mouth-piece, or
other part of a casting apparatus, in the manner above set forth.

page_text: Eleventh. The combination of porcelain clay and black lead crucible
mixture, or its component parts, for useful purposes in the art of manu-
facturing metal and metal compositions.
In witness whereof, I, the said George Haseltine, have hereunto
set my hand and seal, the Eighth day of January, in the
year of our Lord, One thousand eight hundred and seventy-
six.
GEORGE HASELTINE. (L.S.)
Witness,
0' ROWLAND GEORGE BROWN,
8, Southampton Buildings,
London.