IMPROVEMENTS IN AND RELATING TO GUN-. POWDER
Year: 1882

page_text: PROVISIONAL SPECIFICATION left by William Robert Lake at the Office of
the Commissioners of Patents on the 9th June 1882. Communicated to
him from abroad by Norman Wiard, of Washington, District of Columbia,
United States of America.
"
WILLIAM ROBERT LAKE of the firm of Haseltine Lake & Co Patent Agents
Southampton Buildings London IMPROVEMENTS IN AND RELATING TO GUN-.
POWDER [A communication to him from abroad by Norman Wiard, of
Washington, District of Columbia, United States of America.]
This invention relates to gunpowder made in blocks or pieces in the form of
prisms tubes or otherwise which blocks or pieces I will hereinafter refer to as
grains.
Heretofore such gunpowder has been made with the grains compressed upon
their outer surfaces only to produce a desired density Powder so made presents.
the greatest or exterior surface area of burning surface, at the initial ignition of
the charge, and as the grains burn and decrease in size the combustion-surface
correspondingly decreases so that the greatest gas-producing capacity of the charge
of powder is at, or immediately after, the initial ignition of the charge, when the
inertia of the shot has not been overcome or when the shot has started to move at
a very low velocity and the production of gas from that instant decreases until the
entire charge is converted into gas. There results from this operation the greatest
strain on the gun at the moment of the impact of the powder charge upon the
projectile, and from the moment the inertia of the projectile is overcome until it
leaves the muzzle of the gun the rapidity of the production of gases from the.
powder charge is constantly on the decrease, being the reverse of the conditions.
necessary to produce the best results.
The object of this invention is to overcome the objections above named and has
for its object to produce gunpowder which, in its combustion, will first overcome
the inertia of the projectile and thereafter produce gases with such rapidly increasing
volumes as will accelerate the travel of the projectile through the bore of the gun
and give the highest pressure and greatest velocity if desired when the projectile
leaves the muzzle or at that part of the length of the bore which will impart the
highest velocity to the projectile with a given quantity of powder burned within

page_text: a bore of given capacity,-conditions which my improved powder herein described,
by or through its adjustability to differing rates of development of gases, is intended
to accommodate
My invention comprises the following features viz.-
-a perforated grain of
gunpowder having a greatly increased density on its outer surface, whereby the
grain under combustion from all its surfaces will burn most slowly from those
surfaces which are being reduced in area and most rapidly from those surfaces
which are being increased in area as the combustion progresses; also a perforated
grain. of gunpowder provided with an incombustible jacket covering all those
surfaces which would be reduced in area as the grain is consumed and prepared
with increased density at the surfaces where the combustion begins, and gradually
reduced density toward the portion of the grain where the combustion terminates;
Also a grain of gunpowder of a tubular form provided with a tapering perforation;
also a series of perforated grains of gunpowder of a tubular form each covered with
a non combustible jacket, having the qualities hereinbefore mentioned, laid together
and surrounded and secured within an incombustible open end tube
I provide an elongated grain of gunpowder having a tapering opening or per-
foration. The density of the exterior of this grain is greater than the density of
the interior and the variation is made in such a ratio that when the grain is under
combustion the gas-producing capacity of the interior surface is, at the initial
ignition, equal to the gas-producing capacity of the exterior or greater surface, and
as the interior surface increases in area and the exterior surface decreases, the
combustion attacks the intermediate portion of the grain, which, being of less
density than the surfaces, burns with much greater rapidity and evolves an
accelerated volume of gas.
According to another means for reaching this accelerated evolution of gas from
the combustion of the grain, I provide the exterior of the grain with a comparatively
incombustible jacket and make the greatest density of the grain at its interior
surface so that the combustion at the initial ignition attacking only the interior
surface of the grain is comparatively slow and increases with great rapidity towards
the exterior of the grain and there is a corresponding rapidity of the increase of
gases evolved.
For use these grains of powder are laid up in cylindrical bundles or fagots
corresponding in diameter to the bore of the gun in which they are to be used,
with the larger ends of the tapering perforations all at the same end of the package
and this package is surrounded by any desirable wrapper to keep the grains in
position thereby forming a powder cartridge.
In loading, the cartridges are inserted with the smaller ends of the perforations
towards the breech of the gun and the firing charge or fulminate flashes through
the perforations and fires the individual grains primarily from their interior
surfaces The tapering form of the perforations, the larger ends being next to the
projectile, provides for a free escape of gases in that direction and prevents the
fracture of the grains from internal pressure.
When it is designed to burn the grain from both surfaces the hot gases rebound
over the exterior surfaces of the grains and ignite them.
Modifications for applying the same varying density of surface to spherical
powder particularly adapted for great guns and modifications required to adapt
my invention for use in fowling pieces will be readily understood.