Year: 1887

page_text: Date of Application, 11th Jan., 1887
Complete Left, 10th Oct., 1887
Complete Accepted, 2nd Dec., 1887
1, ALEXANDER MELVILLE CLARK, of the firm of A. M. and Wm. Clark, of
53, Chancery Lane, in the County of Middlesex, Fellow of the Institute of Patent
Agents, do hereby declare the nature of the said Invention a communication to me
from abroad by Silvius George Auguste Depout of 11 Boulevard Magenta, Paris
France, to be as follows:-
This Invention relates to the manufacture of a substitute for ivory more especially
intended for making billiard balls. The process consists essentially in agglomerating
sawdust of the maple tree, previously prepared in a suitable manner, the agglomerating
material employed being preferably resin or gum lac. To obtain a white product
cobalt white is employed diluted in hot water with fine glue, while for a red product
carmine is used in preference. A superior white product is obtained by boiling the
sawdust for five hours in a bath of oxygenated water, and after drying triturating it
as above described.
In order to render the material compact, solid, and hard, it is subjected to pressure
in a heated steel mould by means of a hydraulic press. The block is removed from
the mould when perfectly cold, and now ready to be made into balls in the same
manner as real ivory, after which the balls are polished with whiting and colza oil and
immersed in a bath of hot wax in the same way as meerschaum pipes are waxed, then
chucked in a lathe, and wiped, first with a piece of old cloth and afterwards with wash
leather.
A. MELVILLE CLARK.
By A. M. & Wm. Clark,
53, Chancery Lane, London,
Patent Agents.

page_text: An improved manufacture of Artincial ivory.
I ALEXANDER MELVILLE CLARK, of the firm of A. M. and Wm. Clark, of
53 Chancery Lane in the County of Middlesex, Fellow of the Institute of Patent
Agents, do hereby declare the nature of this Invention (a communication to me
from abroad by Silvius George Auguste Depont, of 11 Boulevard Magenta, Paris,
France) and in what manner the same is to be performed, to be particularly described
and ascertained in and by the following statement :-
This Invention relates to the manufacture of an artificial substitute for white or
stained ivory applicable for all the various purposes for which natural ivory is used.
Amongst these various applications the manufacture of billiard balls may be especially
mentioned as involving special conditions as regards homogeneity and density. The
process will therefore be described as carried out for the manufacture of a product
suited for this particular purpose which is the most difficult of attainment, but it will
be understood that in making a product intended for other purposes not involving such
rigorous conditions, a certain degree of latitude or modification in the details of the
process will be admissible, as will be readily understood.
The process consists essentially in agglomerating sawdust of hard wood such as
maple (previously prepared by bleaching if necessary) with an agglutinating material
and a coloring matter if required, and subjecting the mass to heat and pressure,
whereby the sawdust and agglutinant are caused to undergo a chemical change and
are converted into a dense, hard compact body having, with the exception of the grain,
all the characteristics of natural ivory.
If a white product is to be obtained, the sawdust is first boiled for about five hours
in oxygenated water in order to bleach it. It is then thoroughly dried in a room
heated to about 200° to 220° Fah. and afterwards ground fine and thoroughly blended.
It is then mixed with an agglutinating material, preferably resin or gum lac in
alcoholic solution and warmed in the proportion of from 25% to 75% by weight of
agglutinating liquid (according to the desired specific gravity of the product), and
also with about from 5% to 10% of a coloring matter. To produce a white product,
either flake white zinc oxide or a soluble mixture of precipitated chalk with cobalt are
employed, according to the shade it is desired to obtain, and other appropriate coloring
matters (usually aniline colors) in other cases. The mixture having been dried in a
warm room and again ground is then filled in a dry pulverised condition into a steel
mould heated by steam at 40 lbs. pressure and is compressed therein into a solid block,
the pressure being applied by a succession of sudden impacts, the increase of pressure
being meanwhile maintained until the next increment of pressure is applied, and so a
on until the final pressure amounts to about 10 or 12 tons per square inch of the area
of the mould. A mould suitable for the purpose is shown in the accompanying
drawing, in which Figure 1 is a vertical section of the complete mould, and Figure 2
a plan of the outer casing. A screw press designed especially for the above purpose

page_text: forms the subject of another application for Letters Patent made by me on the
thirtieth day of September, 1887, No. 13,267.
The material when compressed to the desired density is allowed to remain under
the maximum pressure in the heated mould for a few minutes and the mould is then
cooled down with water or cold air. It may be then removed from the mould and
sawn into pieces which are then turned and polished in the usual way of turning
billiard balls of real ivory. Instead however of employing the usual process of
polishing, I may employ the process of enamelling described in another application
for Letters Patent made by A. de Pont dated the 10th day of January 1887, No. 383,
in which case the preliminary bleaching of the sawdust and the admixture of a
coloring matter therewith, are unnecessary.
Having now particularly described and ascertained the nature of the said inven-
tion and in what manner the same is to be performed, I declare that what I claim is:―
The manufacture of an artificial substitute for ivory by agglomerating sawdust of
hard wood with an agglutinating material, and subjecting the same to heat and
pressure, substantially as herein described.
A. MELVILLE CLARK.
By A. M. & Wm. Clark,
53, Chancery Lane,
Patent Agents.