AN IMPROVEMENT IN THE MANUFACTURE OF GUNPOWDER
Year: 1864

page_text: LETTERS PATENT to Henry Edwin Drayson, of Southampton, in the
County of Hampshire, Gunpowder Manufacturer, for the Invention
Sealed the 14th June 1864, and dated the 4th February 1864.
PROVISIONAL SPECIFICATION left by the said Henry Edwin Drayson at
the Office of the Commissioners of Patents, with his Petition, on the
4th February 1864.
I, HENRY EDWIN DRAYSON, of Southampton, in the County of Hampshire,
Gunpowder Manufacturer, do hereby declare the nature of the said Invention
for "AN IMPROVEMENT IN THE MANUFACTURE OF GUNPOWDER," to be as follows:-
At present the composition or charge of gunpowder, which is composed of
the proper proportions of saltpetre, sulphur, and charcoal mixed together is
placed under the runners of the incorporating mill, there to be manipulated
for a period of time, and occasionally moistened with hot or cold water until it
is in a fit state to be removed, and is then called mill cake; the mill cake
thus made is then pressed under a heavy pressure in thin cakes, called press
cake, and afterwards granulated by means of machinery into grain.

page_text: Now my improvement consists in passing steam through the composition or
charge for the purpose of bringing it into a state of paste (before it is placed
under the runners in the incorporating mill) which process forms the com-
position or charge into a more adhesive substance and better adapted to
produce grains of powder. This paste or composition when removed from the
vessel, in which it has been submitted to the action of steam, is immediately
placed under the runners of the incorporating mill, where it undergoes the
process of manipulation until it is in a fit state to be removed, and is then
called mill cake, it is then taken from the incorporating mill and immediately
passed through sieves of the required mesh to form grains of powder before
the mill cake becomes dry, set, or hard, the grains thus produced after falling
into a barrel or tub are removed and spread out to dry, when sufficiently dry
they are glazed in the usual way.
I claim as my Invention the passing of steam through the composition or
charge of powder for the purpose of imparting to it an adhesiveness for the
better production of grain, and passing the same through sieves immediately it
is removed from the incorporating mill (after being manipulated the proper,
time) to form grains of powder before the mill cake becomes dry, set, or
hard.
SPECIFICATION in pursuance of the conditions of the Letters Patent, filed
by the said Henry Edwin Drayson in the Great Seal Patent Office on the
1st August 1864.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, HENRY
EDWIN DRAYSON, of Southampton, in the County of Hampshire, a Gunpowder
Manufacturer, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her Letters
Patent, bearing date the Fourth day of February, in the year of our
Lord One thousand eight hundred and sixty-four, in the twenty-eighth year
of Her reign, did, for Herself, Her heirs and successors, give and grant unto
me, the said Henry Edwin Drayson, Her special licence that I, the said Henry
Edwin Drayson, my executors, administrators, and assigns, or such others as I, the
said Henry Edwin Drayson, my executors, administrators, and assigns, should at
any time agree with, and no others, from time to time and at all times there-
after during the term therein expressed, should and lawfully might make, use,
exercise, and vend, within the United Kingdom of Great Britain and Ireland,

page_text: the Channel Islands, and Isle of Man, an Invention for "AN IMPROVEMENT IN
THE MANUFACTURE OF GUNPOWDER," upon the condition (amongst others) that I,
the said Henry Edwin Drayson, my executors or administrators, 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 Henry Edwin Drayson, do hereby declare
the nature of my said Invention, and in what manner the same is to be per-
formed, to be particularly described and ascertained in and by the following
statement:
At present the composition or charge of gunpowder which is composed of
the proper proportions of saltpetre, sulphur, and charcoal mixed together is
placed under the runners of the incorporating mill in a dry state, or the charge
is submitted to a jet of steam for the purpose of dissolving the saltpetie
previous to its being placed under the runners (see Hodges' Patent, No. 2227,
1857). Another method is by dissolving the saltpetre by hot water and mixing
the sulphur and charcoal with the saltpetre so dissolved before undergoing
manipulation in the mill (see Drayson's Patent No. 2427, 1855,) and by a
Patent process taken out (see Willett's Patent No. 1313, 1856,) a steam jet
is thrown upon the charge during the operation of grinding it in the mill and
submitting a blast of air upon the said charge to dry up the moisture which
the said jet of steam had previously imparted to it; after the composition or
charge has undergone its proper period of time in being ground in the mill, it
is then removed, and is then called mill cake; the mill cake thus made is taken
to the press house, where it is placed in a large press box in layers, having
metal plates placed between each layer for the purpose of pressing the mill
cake into thin cakes, called press cake; it is then removed and taken to the
corning house, where it is broken down into grain and dust, by means of
complicated machinery having many brass, gun metal, or zinc rollers, through
which the press cake is passed, in the proportion of about three-fourths grain
and one-fourth dust, the dust is again taken back to the incorporating
mill, to be reworked into mill cake, repressed and regranulated into grain and
dust, or in some cases the mill cake is taken direct to the granulating machine
and reduced in the proportion of two-thirds grain to about one-third dust, the
dust thus produced is either taken to the mill to be reworked, or is placed in
the press to be pressed with mill cake, and again re-granulated, causing the

page_text: same operation to be frequently repeated over a portion of the material for an
almost indefinite period of time.
Now according to my process I do not allow a sufficient quantity of steam
to pass through the vessel to dissolve the saltpetre and soften the sulphur, as
described in the Specification to the Patent granted to Henry Hodges,
No. 2227, 1857, for " Improvements in the Manufacture of Gunpowder
before referred to, and in which I hold a right of user and option of sale to the
Crown by a deed of assignment bearing date the 24th day of July, 1858, but
I only allow sufficient steam to pass through the composition or charge before
it is placed under the runners of the incorporating mill, as to make it a more
adhesive substance, this better prepares the mill cake to be formed into grain..
The steam is first admitted to the box or suitable vessel, which box or vessel,
may be made of wood or any other material, with or without a lid, the com-
position is then placed therein, where it remains only a sufficient time for the
steam to pass through it, when this is effected it is then placed on the mill bed
to be ground, and when sufficiently ground it is removed, and is then called
mill cake; immediately on its removal from the mill bed, and before it becomes
dry, set, or hard, it is passed through a sieve or sieves of the required mesh to
form grains, large and small, of powder, the grain thus produced after passing
through the sieve or sieves into a barrel or tub is removed and spread out to
dry, the whole of the mill cake being formed into grain there is no dust to be
reworked; when the grain is sufficiently dry it is glazed in the usual way. If
the grain so formed is very angular, and a more rounded grain is required, a
rotatory motion is given for a few seconds to the last sieve in which the grain
is placed, it is then removed and spread out to dry and afterwards glazed in
the usual way, these operations must be carried on before the mill cake or
grain made from the mill cake becomes dry, set, or hard.
Now I wish it to be understood that I do not claim as any part of my
Invention the passing of steam into a vessel for the purpose of dissolving the
saltpetre and softening the sulphur, nor do I by my process dissolve the
saltpetre and soften the sulphur, but I only allow a sufficient quantity of steam.
to pass into the vessel to add an adhesiveness to the composition, which cannot
be otherwise obtained, to prepare it for the runners of the incorporating mill,.
and ultimately granulation by the process herein-before described, and which is
in fact the substance of my Patent, and which I claim to be new. I claim
the passing of the mill cake through a sieve or a series of sieves of any.
required mesh, after it has been removed from the mill bed, for the purpose
of forming it into grain, before the mill cake becomes dry, set, or hard, and.

page_text: giving the last sieve in which the said grain is placed a rotatory motion before
the said grain becomes dry, set, or hard, reducing the whole of the mill cake
into grain and leaving no dust behind.
In witness whereof, I, the said Henry Edwin Drayson, have hereunto
set my hand and seal, this Twenty-ninth day of July, in the year of
our Lord One thousand eight hundred and sixty-four.
HENRY EDWIN DRAYSON. (L.S.)