IMPROVEMENTS IN ORDNANCE."
Year: 1871

page_text: LETTERS PATENT to Josiah Harris, of No. 8, Old Jewry, in tho
City of London, Engineer, for the Invention of "IMPROVEMENTS IN
ORDNANCE."
PROVISIONAL SPECIFICATION left by the said Josiah Harris at the
Office of the Commissioners of Patents, with his Petition, on the
21st April 1871.
I, JOSIAH HARRIS, of No. 8, Old Jewry, in the City of London,
Engineer, do hereby declare the nature of the said Invention for
"IMPROVEMENTS IN ORDNANCE," to be as follows (that is to say)
This Invention which may be applied to any description of gun
consists in exhausting the air from the bore of the gun in front of the
charge, so that the projectile being freed from the pressure of the
atmosphere on its front surface a much less charge of powder will be
required to impel it from the gun at any given velocity than would

page_text: ordinarily be necessary, whilst if the usual charge of powder be used
the projectile will be impelled at a greater velocity than would be the
case with the pressure of the atmosphere on its front surface.
The following is a simple method of carrying my Invention into
effect. After the gun has been charged I place over the muzzle an
air-tight cap made of india-rubber or other suitable material, and if
necessary strengthened with plates of wood or metal. Through this
cap passes a tube of suitable material and construction, one end of
which communicates with the bore of the gun and the other with an
air pump,
which being actuated by any suitable means will exhaust the
air contained in the bore of the gun between the charge and the said
air-tight cap, and when this has been effected, either wholly or to a
sufficient extent, the gun is fired off in the usual manner.
In order to prevent the passage of air through the touch-hole into
the bore of the gun I provide the wad, which is rammed home to the
charge of powder and remains between the powder and the projectile,
with a valve opening outwards or towards the muzzle of the gun, so that
whilst the said wad is being forced into position any air that may be
behind it will pass out through the said valve, which is so formed that
on the projectile being rammed home it will close the said valve and
thus prevent any further passage of air. The air-tight cap hercin-before
alluded to may be made either to be blown away when the gun is fired
or be attached to the gun by a chain or other suitable means, the tube
passing through it and connected with the air pump being made weak
near the muzzle of the gun by any suitable means, so that if the said
cap be blown away, connection with the air pump may be readily
established with the next cap to be used.
I would observe that I do not confine myself to the method above
described for exhausting the air as various other means may be employed.
For example, the tube communicating with the bore of the gun may be a
introduced through the trunnions of the gun instead of through the
said cap, whilst on board ship it may communicate with the steam
condenser which will give the required vacuum without the aid of the
air pump.

page_text: van puistance of the Contions of the Letters Patent,
filed by the said Josiah 'Harris in the Great Seal Patent Office
on the 21st October 1871.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, JOSLAK
HARRIS, of No. 8, Old Jewry, in the City of London, Engineer, send
greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her
Letters Patent, bearing date the Twenty-first day of April, in the year
of our Lord One thousand eight hundred and seventy-one, in the thirty-
fourth year of Her reign, did, for Herself, Her heirs and successors,
give and grant unto me, the said Josiah Harris, Her special licence that
I, the said Josiah Harris, my executors, administrators, and assigns,.
or such others as I, the said Josiah Harris, my executors, adminis-
trators, 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 Ordnance,”
upon the condition (amongst others) that I, the said Josiah Harris,
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 Scal Patent Office within six calendar months next and imme-
diately after the date of the said Letters Patent.
NOW KNOW YE, that I, the said Josiah Harris, do hereby declare
the nature of my said Invention, and in what manner the same is
or may be performed, to be particularly described and ascertained in
and by the following statement :-
This Invention, which may be applied to cither breech or muzzle
loading guns, consists in exhausting the air from the bore of the gun in
front of the charge, so that the projectile being freed from the pressure
of the atmosphere on its front or outer surface, a much less charge of
powder or other explosive will be required behind it to impel it from
the gun at any given velocity than would ordinarily be necessary, whilst
if the usual charge of powder be used the projectile will be impelled at

page_text: a greater velocity than would be the case with the pressure of the
atmosphere on its front surface.
And in order that my Invention may be clearly understood and
readily carried into effect, I now proceed to describe the same with the
aid of the accompanying Drawings, reference being had to the letters
and figures marked thereon. In each case the same letter wherever it
occurs indicates the same part or parts.
Fig. 1 represents a longitudinal section of a muzzle-loading gun with
the charge rammed home, and with my improvements applied, and
Figs. 2, 3, 4, and 5, represent different views of parts of my apparatus.
In order to exhaust the air from the bore of the gun (A, Fig. 1) in
front of the charge I place over the muzzle (B) of the gun an air-tight
cap (C) made of india-rubber or other suitable substance, and when
necessary stiffened by a plate (D) of metal or other suitable substance
or material. Detached views of this cap are shewn at Figs. 2, 3, and 4.
Through this cap (C) passes a tube (E) communicating with the bore
of the gun, the other end of which tube is led to an air pump of any
known construction, and situated as circumstances may require or render
desirable. This pump being actuated by any suitable means will exhaust
the air from the bore of the gun, and thus relieve the projectile (F)
from the pressure of the atmosphere on its front surface, and when this
has been effected either wholly or to a sufficient extent the gun is fired
off in the usual manner. The said tube (E) is constructed in two parts,
that portion (e¹) leading from the air pump to some point (H) near the
cap (C) being made strong and permanent, and the other part (e²)
between the said point (H) and the cap (C) to which it is attached being
made weak so as to be readily carried away with the cap (0) at the
discharge of the gun. The union between these two parts of the
tube (E) is effected by an elastic band (M) or by any other ready and
efficient means so as to render connection with the cap to be used for
the next discharge capable of being readily effected.
In order to prevent the passage of air through the vent or touch-hole
into the bore of the gun in front of the charge where the vacuum is
required I provide the wad (J, Figs. 1 and 5,) which is rammed home to
the charge of powder (K), and remains between it and the projectile with
a valve (L) opening outwards or towards the muzzle of the gun, so that
whilst the wad is being forced into position the air between it and the
powder will pass out through the said valve (L) which is so formed that

page_text: on the projectile being rammed home it will close the valve and thus
prevent any passage of air.
To render this Invention effective when applied to breech-loading
guns it is only necessary to ensure that the breech be perfectly air-tight
when the charge is inserted and the breech closed.
I would observe that I do not confine myself to the form of сар
hercin-
described nor to the material of which it shall be made, nor to the incans
shewn of attaching it to the gun, neither do I limit myself to the details
herein described for exhausting the air from the gun and maintaining
the vacuum whilst necessary, as all the details herein set forth for
carrying my Invention into effect may be subject to various modifications
without departing from the principle of the Invention. For example,
communication with the bore of the gun may be effected through one
of the trunnions instead of through the cap as herein-before described,
and in some cases, as for instance on board a man of war, or when in
batteries the pipe communicating with the bore of the gun and through
which the air is exhausted may be led to the condenser of a steam
engine, thus obtaining the required vacuum without the aid of the air
pump, but what I claim as my Invention and desire to secure by the
herein-before in part recited Letters Patent is, exhausting the air from
the bore of the gun in front of the charge in the manner and for the
purpose herein-before set forth and described.
In witness whereof, I, the said Josiah Harris, have hereunto set
my hand and seal, this Twentieth day of October, in the year of
our Lord One thousand eight hundred and seventy-onc.