In- PROVEMENTS IN THE MANUFACTURE OF GUNPOWDER
Year: 1856

page_text: LETTERS PATENT to Thomas William Willett, of 89, Chancery Lane, in
the County of Middlesex, Civil Engineer, for the Invention of "In-
PROVEMENTS IN THE MANUFACTURE OF GUNPOWDER."
Scaled the 19th August 1856, and dated the 3rd June 1856.
PROVISIONAL SPECIFICATION left by the said Thomas William Willett
at the Office of the Commissioners of Patents, with his Petition, on the
3rd June 1856.
I. THOMAS WILLIAM WILLETT, of 89, Chancery Lane, in the County of
Middlesex, Civil Engineer, do hereby declare the nature of the said Invention
for "IMPROVEMENTS IN THE MANUFACTURE OF GUNPOWDER," to be as follows:-
At present when it is desired to moisten the charge in an incorporating
gunpowder-mill it is done by the addition of hot or cold water applied to the
charge, either by hand, with a small watering-pot, or by suitable apparatus
attached to the mill, for supplying a stream, the amount and temperature of
which can be regulated at pleasure..
Now, my first improvement consists in the direct application of a jet or
jets of steam to the charge of powder while in the mill, by which means the
charge is more regularly and evenly moistened than by the application of
water. These jets of steam are caused to issue either from pipes attached to
certain stationary parts of the mill, or (which I prefer) from pipes revolving

page_text: with the runners or rollers, the steam being supplied to such revolving pipes
by suitable mechanical arrangements, as are well understood.
My second improvement consists in the application of an artificial current
of air to the interior of an incorporating gunpowder-mill, for the purpose of
drying the charge. This current of air I pefer to conduct by fixed pipes to
the interior of the mill, but it may be made to issue from revolving pipes,
similar to those described as above, for the application of tho steam; but in
either case I prefer so to arrange this current that it does not forcibly impinge
upon the surface of the charge, but only pass gently over it. This current of
air may be caused by a fan or other suitable means, and it may be artificially
lieated if desired.
In witness whereof, I, the said Thomas William Willet, have hereunto
set my hand, this Third day of June, in the year of our Lord One
thousand eight hundred and fifty-six.
SPECIFICATION in pursuance of the conditions of the Letters Patent, filed
by the said Thomas William Willett in the Great Seal Patent Office
on the 25th November 1856.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, THOMAS
WILLIAN WILLETT, of 89, Chancery Lane, in the County of Middlesex, Civil
Engineer, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her Letters
Patent, bearing date the Third day of June, in the year of our Lord
One thousand eight hundred and fifty-six, in the nineteenth year of Her reign,
did, for Herself, IIer heirs and successors, give and grant unto me, the said
Thomas William Willett, Her special licence that I, the said Thomas
William Willett, my executors, administrators, and assigns, or such others
as I, the said Thomas William Willett, 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 MANUFACTURE OF GUNPOWDER," upon the condition
(amongst others) that I, the said Thomas William Willett, 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

page_text: 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 Thomas William Willett, do hereby
declare the nature of my said Invention, and in what manner the same is to
be performed, to be particularly described and ascertained in and by the
following statement:-
At present when it is desired to moisten the charge in an incorporating
gunpowder mill it is done by the addition of hot or cold water applied to the
charge, either by hand, with a small watering pot, or by suitable apparatus
attached to the mill, for supplying a stream of water, the amount and the
temperature of which can be regulated at pleasure.
Now, my first improvement consists in the direct application of a jet or
jets of steam to the charge of powder while in the mill, by which means the
charge is more regularly and evenly moistened than by the application of
water. These jets of steam are caused to issue either from pipes attached to
certain stationary parts of the mill, or (which I prefer) from pipes revolving
with the runners or rollers.
My second improvement consists in the application of an artificial current
of air to the interior of an incorporating gunpowder mill, for the purpose of
drying the charge at the proper stage in the manufacture. The current of
air I prefer to conduct by stationary pipes to the interior of the mill,
but it may be caused to issue from pipes revolving with the runners or
rollers; but in either case I prefer so to arrange the current that it does not
forcibly impringe upon the surface of the charge, but only pass gently over it.
Having thus stated the nature of my Invention, I will proceed to describo
more fully the manner of performing the same, reference being had to the
Drawing hereunto annexed.
Fig. 1 represents a portion of an incorporating gunpowder mill. The mill
bed B, with its surrounding woodwork R and the masonry C, (upon which
the mill is erected,) are shown in section. I may here observe, that for the
purposes of my Invention I prefer that construction of mill in which the stone
shaft is driven from beneath the mill bed, but my Invention may be readily
adapted to other mills.
A is the runner; F, the runner shaft, a portion of which with one of the
runners is removed; S, S, is the steam pipe, attached to the beam U by the
clips T, T. The steam pipes S passes into the stuffing box K of the small
steam chest G, which is attached to the head E of the driving shaft D, and

page_text: whichi, therefore, revolves with the runners.
From this steam chest G pass
two steam pipes II, II, which terminate on two other small steam chests
K', K. These steam chests I prefer to make in length about four inches
less than the width of the mill bed, and in width from seven to eight.inches,
according to the size of the mill. The bottom of these steam chests K³, K',
is perforated with small jets or pipes L, L, the arrangement of which will be
better seen by reference to Figure 2, in which W is the bottom. of the steam
chest K', (by preference of strong sheet copper,) and V, V, V, the small'steam
pipes. Tliese are made to rise about three quarters of an inch into the
interior of the steam chest, the object of which is to allow the water of con
densation to collect in the bottom of the chest instead of falling upon the
charge. I, I, are two stop cocks, by which the amount of steam supplied can
be regulated at pleasure. M is hollow pipe, resting upon the central block N,
and connected with the pipes P, P. Air from a fanner or other suitable
apparatus is conducted by these pipes P, P, to the hollow pipe M, whence it
issues through the small apertures m, m, m. These apertures should be
placed as near the bottom of the hollow pipe M as possible, so that the current
of air issuing from them may be deflected by the central block N, and com-
pelled to pass above the surface of the charge, so as to ventilate and dry the
same, and yet not to cause it to rise as dust. This current of air (which may
be heated with advantage in damp weather) must be regulated at the discre-
tion of the mill man, according to the state of the charge; but in all cases
the current must be very gentle, and such as not to raise the charge in dust.
In those cases where it is required to hasten the drying of a charge to an
extent that would by the above-described arrangement cause the dust to rise,
I prefer to reverse the direction of the current, and by exhausting the air from
the hollow pipe M, by means of a fanner or other suitable apparatus in con-
nexion with the pipes P, P, I create a current of air over the surface of the
charge, but the dust that is then raised is for the most part carried towards
the openings m, m; m, which should be covered with a thin woollen cloth to
prevent the ingress of the powder.
..:
In constructing a mill in which this reversed current alone is to be used
for the purpose of drying the charge, I make the hollow pipe M of greater
size, and the apertures m, m, more numerous, and in such case I do not employ
any woollen cloth over them, but allow the powder dust to enter freely and
pass along the pipe P', which is then made to terminate in a water chamber,
constructed on the plan of a Turkish water pipe, and the whole, therefore, of
the dust that is carried with the current along the pipe P¹ is thus detained in
the water. It will be obvious that this ventilating M might be arranged on

page_text: the outer instead of the inner margin of the mill bed, or that the current of air
(forward or reversed, as before described,) might be applied by an apparatus
similar to that I employ for the application of the jets of steam, and similarly
the steam might be applied by the apparatus I have here described as suited
for the application of the current of air; but I prefer the arrangements I have
shewn, for in all cases I think it desirable that the steam issuing from the steam
jets should directly and more or less forcibly impinge upon the charge; and, on
the other hand, I think that the air current should not impinge upon it, but
only pass gently over its surface.
In witness whereof, I, the said Thomas William Willett have hereunto
set my hand and seal, this Twenty-fifth day of November, in the year
of our Lord One thousand eight hundred and fifty-six.
THOMAS WILLIAM WILLETT. (L.S.)