PRODUCING IMITATIONS OF AND SUBSTITUTES FOR WOOD, IVORY, STONE, AND OTHER HARD SUBSTANCES APPLICABLE TO THE MANUFACTURE OF BILLIARD BALLS AND OTHER ARTICLES,
Year: 1869

page_text: PROVISIONAL SPECIFICATION left by John Henry Johnson at the
Office of the Commissioners of Patents, with his Petition, on
the 25th May 1869.-A communication from abroad by David
Blake, of Albany, State of New York, in the United States of
America.
I, JOHN HENRY JOHNSON, of 47, Lincoln's Inn Fields, in the County
of Middlesex, Gentleman, do hereby declare the nature of the said
Invention for "PRODUCING IMITATIONS OF AND SUBSTITUTES FOR WOOD, IVORY,
STONE, AND OTHER HARD SUBSTANCES APPLICABLE TO THE MANUFACTURE OF
BILLIARD BALLS AND OTHER ARTICLES," a communication to me from abroad
by David Blake, of Albany, State of New York, in the United States of
America, to be as follows:-
This Invention relates to the production of imitations of or substitutes
for wood, ivory, stone, and other hard substances, and is specially
applicable to the manufacture of billiard balls and other like articles.
In carrying out this Invention I take any kind of fibrous, vegetable,
animal, or even mineral matter, such for instance as flock paper, leather
chips, or asbestos, and reduce the same to a very fine state so that the

page_text: particles can be intimately and thoroughly mixed with a pulverized
cementing or aglutinizing substance.
I have been very successful in the use of paper pulp, or paper reduced
by grinding to a very fine flock, but do not confine myself to the use of
this substance, as almost any fibrous substance will answer the purpose
when properly reduced. I also use gum lac or any other solid fusible
and adhesive gum or substance, which may be found to answer the
required purpose and reduce the same to a very fine powder. This
cement I thoroughly intermix with the fibrous substance, both being in
as dry a state as possible. The proportions of the cementing substance
and the fibrous material are about equal in quantity by weight, although
I do not confine myself to these proportions as they will vary according
to the solidity and strength required in the moulded article. In the
process of moulding this composition into useful forms I apply heat and
pressure. The heat is designed to fuso the shellac or other cementing
substance used in the compound, and to cause it to cement the small
fibres firmly together and form a solid homogeneous body. To this end
such a degree of heat should be applied as will effect the desired result.
The pressure which is applied simultaneously with the heat is to
compress and pack the mass together and thus form a very dense body.
It is also important during the operation of moulding to keep the
mass under pressure until has set, or in other words until the fusible
cement is cool and hard so that the article moulded will not expand or
change its shape. When desirable the specific gravity of the article can
be regulated by adding white lead or other suitable pigment to the
compound before it is moulded. For some articles I use ivory dust,
bone dust, or other suitable powdered substances, and aglutinize them
together with a solution of pyroxiline, putting the compound so formed
into moulds where it is subjected to heat and great pressure. In order
to improve the appearance and quality of the surface of the billiard ball
or other article I apply a coating of pyroxiline and some of its com-
pounds. This coating is applied either by dipping the ball into a
solution of the pyroxiline colored by the addition of any suitable coloring
matter, or by moulding the same on to the surface of the ball. Or the
coloring matter may be subsequently applied.
My process of moulding is as follows:-I first take the soluble gun
cotton and dissolve it in ether and alcohol or any of its known solvents,
using only enough of the solvents to make the mass into a thick plastic

page_text: state. I then employ a cylinder which contains a forcing piston. The
plastic mass is placed in the cylinder between the piston and the head
of the cylinder. In the head of the cylinder is a nozzle leading into a
mould of a suitable size and shape. During the operation of moulding
thic piston is forced by any suitable application of power (such as a screw
and lever) against the plastic mass forcing it through the nozzle into the
mould attached thereto and containing the article to be coated. For
billiard balls the mould is formed with a smooth and spherical cavity of
proper size and is made to part in sections to allow the moulded ball
to be removed. In the side of the mould opposite the orifice connecting
with the nozzle on the cylinder I place three adjustable pins or set
screws, against the ends of which the ball rests so as to be kept
cquidistant from all sides of the mould while the plastic mass is being
forced into the mould and around the ball, so as to insure an even
thickness of the coating on the entire surface. At a point opposite the
inlet of the mould I have a vent hole to allow the air in the mould and
a portion of the plastic mass to pass out so that the coating may become
perfectly united. After this the vent is closed and the adjustable pins
or set screws are retracted till their ends are flush with the interior
surface of the mould when a slight additional pressure will fill the
cavities left by the ends of the adjustable pins, thus making the coating
perfect and entire. For many articles besides billiard balls which do
not require to be coated on the entire surface, the article may be
kept in proper place without the aid of adjustable pins. After the
moulded coating of the billiard ball is allowed to harden it is turned
and polished.