IMPROVE- MENTS. IN THE MANUFACTURE OF ORDNANCE, AND IN THE PROJECTILES TO BE USED THEREWITH
Year: 1855

page_text: LETTERS PATENT to Henry Bessemer, of Queen Street Place, New
Cannon Street, in the City of London, for the. Invention of "IMPROVE-
MENTS. IN THE MANUFACTURE OF ORDNANCE, AND IN THE PROJECTILES TO BE
USED THEREWITH."
Sealed the 11th April 1856, and dated the 17th October 1855.
PROVISIONAL SPECIFICATION left by the said Henry Bessemer at the
Office of the Commissioners of Patents, with his Petition, on the 17th
October 1855.
I, HENRY BESSEMER, of Queen Street Place, New Cannon Street, in the
City of London, do hereby declare, the nature of the Invention for "IMPROVE-
MENTS IN THE, MANUFACTURE, OF. ORDNANCE, AND IN THE PROJECTILES TO BE USED
THEREWITH," to be as follows:-
I
This Invention relates, firstly, to the, preparation of the materials to be used
in the manufacture of cannons, mortars,.. or other ordnance, and consists in
decarbonizing, refined pig. iron by the process of puddling until the greater
part of its carbon is driven off,. enough only being left combined with it to
ensure the complete fusibility of the metal when exposed to a very high
temperature in close, crucibles, such as are generally employed for melting
steel; or in lieu of the metal so treated, I take scrap iron and put it into
crucibles, such as are used for the melting of steel, in which the iron is to be
fused, and which may afterwards be cast into the desired form. It will be found
to greatly facilitate the melting of the iron if charcoal in a state of coarse
powder or other carbonaceous matters. be mixed with the pieces of scrap iron,

page_text: by means of which the iron will be cemented and converted into a very mild
or soft steel. During its fusion, either of these qualities of metal may be
manufactured into ordnance separately, or they may be mixed together in such
proportions as are found most suitable for the particular kind of ordnance to
be manufactured.
The iron or steel having been melted, I proceed to cast it in an ingot mould
made of cast iron, or into a dry loam mould, such as is used in founding iron.
If the casting be intended to produce a cannon, I make the ingot mould of
a particular shape, dependant partly on the after processes to which it is to be
subjected, and partly on the shape which the piece is to have when finished,
and which shapes I distinguish as Nos. 1, 2, and 3: the shape No. 1 is a plain
truncated cone; No. 2, a prism or polygon, also tapering; and No. 3,
circular figure, having rings, mouldings, or other inequalities of surface,
resembling the configuration of an ordinary cannon; in all cases, however, the
trunnions are omitted. The guns thus far formed by founding are then to
undergo a process of pressing or rolling, for the purpose of condensing the
metal and increasing its hardness and power of cohesion. For this purpose I
employ two different kinds of rolling mills. The first one consists of two
rollers of chilled iron, of such size that the circumference of each of them
measures more than the length of the cannon to be operated upon by them.
Around each of the rolls is formed a deep groove, the sides of which are at
such an angle to each other as to form two sides of a polygonal figure; these
grooves are made to form an involute, deepening as the groove proceeds round
the roller, so that the taper polygonal gun, before referred to as No. 2, can be
passed between them, the receding surface of the involute groove allowing
the larger end to pass between them as readily as the small end of it. These
rolls are to be fixed in a strong iron frame with set screws, similar to those in
general use for rolling metals; but the rollers instead of being placed one
above another as usual, are to be placed side by side in the same horizontal
plane, and the gun casting is to be suspended over them by a chain pulley
and counterbalance weight, and be made to descend between the rollers and
again ascend after the largest part of the gun has passed between them. This
process is to be continued until the casting has been sufficiently increased in
length and reduced to the desired diameter; it should be heated to a full
red heat previous to being passed through the rollers, and should be turned
partly round after every time of passing through them, in order to ensure an
equality of compression at all parts. In like manner a pair of rolls having a
circular involute groove of increasing diameter may be made to operate upon
the truncated conical gun casting No. 1.

page_text: The second rolling mill, herein-before referred to, consists of three rolls,
arranged in the following manner :-Two of them are placed side by side,
with their axes in the same horizontal plane, and the third roller is to be placed
above and between them, in a similar manner to the arrangement of rollers
employed in the mills used for crushing sugar canes; the rollers, however,
are not cylinders, but are cones of the same proportions as the casting No. 1,
before referred to; the 3 rollers should be mounted on a strong frame, and be
provided with screws, for the purpose of adjusting their relative position to
cach other. The conical gun casting having been heated to a full red heat, is
placed in between the three rollers, which are then put in motion, the screws
being tightened up, and the rolling continued until the desired amount of
compression of the metal has been effected. When it is intended to perform a.
like process on the gun casting No. 3, the rolls have mouldings or grooves
formed around them, corresponding with the raised mouldings to be formed
on the gun, and thus a due compression of the whole may take place, the
rolled surface giving all the external finish that is necessary except at the
ends, which may be finished in the lathe. In some cases it may be found
preferable to cast the gun hollow, in which case a hard mandril should be put.
into the gun while being operated upon between the rollers. When not cast
hollow, the boring of the gun may take place in a boring mill as usual, either
before or after the rolling process. In some cases it may be found convenient to
allow the bore to extend entirely through the gun, in which case a breech may
be screwed or otherwise fixed into the thick end of the gun. It will be obvious
that in this mode of compressing or rolling ordnance the trunnions cannot be
formed on them as usual. I therefore adopt one of the following methods:-
Firstly, the gun may have a shallow hollow cavity of rather large diameter
formed on either side at the part where the trunnions are usually situated;, I
then form two pieces of steel in such manner as when bolted together they
will embrace loosely the lower side of the gun; these pieces are provided with
lugs and bolts, by which they may be fastened to the gun carriage. There is to:
be formed on each piece a raised circular projection, which fits accurately into.
the shallow cavities made in the sides of the gun, and which are to answer the
purpose of the usual trunnions.
Secondly, I bore a hole in the breech end of the gun, at right angles to its
length, and as far back as will not weaken the gun; through this hole I pass.
a stout steel pin; the ends of the pin are fitted into the eyes of two wrought
iron or steel tension bars, which are sufficiently long to reach that part of
the gun where the trunnions are usually placed, where the tension bars are
to be jointed to a piece of wrought iron or steel, having a central hollow in

page_text: which the gun rests; this piece of steel is to be secured by bolts to the gun
carriage.
And, thirdly, in some cases I form at the part where the trunnions are usually
situated a raised band around the gun; this band is of a spherical form, to
which I adapt a kind of plummer block, opening in two halves, the lower one
being secured by bolts to the gun carriage, and the upper half secured by bolts
to the lower one; this substitute for the trunnion admits of an universal motion
of the gun within given limits. The muzzle of the gun may either be hollowed
out to reduce the pressure at the point of exit, or it may be turned down a little,
and a suitable ring shrunk on it, and secured by rivetting down the metal at
the end; the breech end may be finished in the lathe, and the whole exterior
may be either turned, or in the case of the polygonal gun, finished in the planing
machine.
The great cohesive strength of cast malleable iron or steel as compared
with ordinary cast iron admits of a heavier projectile being used than is usual
with guns as at present constructed; but as the generality of elongated
projectiles are greatly obstructed by the atmosphere, and turned more or less
from their intended direction, unless they are caused to move with their longer
axis in the line of flight; I therefore give such a figure to the projectile as
will cause it to suffer very little deviation or increased resistance from the air,
and which from its increased weight will be found of great service when
battering at a short range; the same figure will also give a corresponding
increase in weight to the charge contained in shells. This form of projectile
would be simply a perfect sphere, of a size too large for the gun, but for the
exception of a flat or cylindric zone made around it, which fits accurately the
bore of the gun. The proportion I recommend is about a 7-inch sphere for a
6-inch gun, which will increase the weight considerably, and at the same
time the extreme deviation from a true sphere will not exceed an inch at
any part; the centre of gravity of such a shot will be the centre of the large
curved surface, and by revolving on this centre the greater part of it will
present to the air the same motion as a common spherical shot.
However, where both a heavier shot and a longer range are required, I form
a hollow cast steel ball, which may be stamped while red hot between dies,
and be thus compressed, and its power of cohesion increased. This ball I fill
with molten lead, the increased specific gravity of which will both increase
its weight and range; both of which modes of increasing the ordinary weight
of the projectile may be safely employed with guns manufactured in the manner
herein-before described.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent, filed
by the said Henry Besseiner in the Great Seal Patent Office on the
17th April 1856.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, 'HENRY
BESSEMER, of Queen Street Place, New Cannon Street, in the City of
London, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her Letters
Patent, bearing date the Seventeenth day of October, in the year of our Lord
One thousand eight hundred and fifty-five, in the nineteenth year of Her reign,
did, for Herself, Her heirs and successors, give and grant unto me, the said
Henry Bessemer, Her special licence that I, the said Henry Bessemer, my
executors, administrators, and assigns, or such others as I, the said Henry
Bessemer, 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 ORDNANCE, AND IN THE PROJECTILES TO BE USED THEREWITH," upon the condition
(amongst others), that I, the said Henry Bessemer, my executors or adminis-
trators, 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 Bessemer, do hereby declare
the nature of the 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 thereof, that is to say:-
This Invention relates, firstly, to the preparation of the materials to be used
in the manufacture of cannons, mortars, or other ordnance, and consists in
decarbonizing refined pig iron by the process of puddling until the greater
part of its carbon is driven off, enough only being left combined with it to
insure the complete fusibility of the metal when exposed to a very high tem-
perature in close crucibles, such as are generally employed for melting steel;
or in lieu of the metal so treated, I take scrap iron and put it into crucibles,
such as are used for the melting of steel, in which the iron is to be fused, and
which may afterwards be cast into the desired form. It will be found to

page_text: greatly facilitate the melting of the iron if charcoal in a state of coarse
powder or other carbonaceous matters be mixed with the pieces of scrap iron,
by means of which the iron will be cemented and converted into a very mild
or soft steel. During its fusion, either of these qualities of metal may be
manufactured into ordnance separately, or they may be mixed together in such
proportions as are found most suitable for the particular kind of ordnance to
be manufactured.
The iron or steel having been melted, I proceed to cast it in an ingot
mould made of cast iron, or into a dry loam mould, such as is used in founding
iron. If the casting be intended to produce a cannon, I make the ingot
mould of a particular shape, dependant partly on the after processes to which
it is to be subjected, and partly on the shape which the piece is to have when
finished, and which shapes I distinguish as Nos. 1, 2, and 3, and which are
represented in side and end elevation at Figures 1, 2, and 3 on the Sheet of
Drawings hereunto annexed. The shape No. 1 is a plain truncased cone;
No. 2, a prism or polygon, also tapering; and No. 3, a circular figure, having
rings, mouldings, or other inequalities of surface, resembling the configuration
of an ordinary cannon; in all cases, however, the trunnions are omitted. The
guns thus far formed by founding are then to undergo a process of pressing or
rolling, for the purpose of condensing the metal and increasing its hardness
and power of cohesion. For this purpose I employ two different kind of
rolling mills. The first one consists of two rollers of chilled iron, of such size
that the circumference of each of them measures more than the length of the
cannon to be operated upon by them. Around each of the rolls is formed a
deep groove, the sides of which are at such an angle to each other as to form
two sides of a polygonal figure; these grooves are made to form an involute,
deepening as the groove proceeds round the roller, so that the taper polygonal
gun, before referred to as No. 2, can be passed between them, the receding
surface of the involute groove allowing the larger end to pass between them
as readily as the small end of it. These rolls are to be fixed in a strong iron
frame with set screws, similar to those in general use for rolling metals; but
the rollers, instead of being placed one above another as usual, are to be
placed side by side in the same horizontal plane, and the gun casting is to be
suspended over them by a chain pulley and counterbalance weight, and
be made to descend between the rollers and again ascend after the largest part
of the gun has passed between them. This process is to be continued until
the casting has been sufficiently increased in length and reduced to the desired
diameter. It should be heated to a full red heat previous to being passed
through the rollers, and should be turned partly round after every time of

page_text: passing through them. In order to ensure an equality of compression at all
parts in like manner, a pair of rolls having a circular involute groove of,
increasing diameter may be made to operate upon the truncated conical gun
casting No. 1.
In order that the mode of making and using the rolls herein described for.
the purpose of rolling a taper prism or cone may be fully understood, I have
represented a pair of such rolls in section at Figure 4 of the annexed Sheet
of Drawings; Figure 5 being a plan of the same, and Figure 6 another section
thereof, shewing the position of the rolls with reference to each other at the
time the casting is being moved upwards. a, a, are the rolls, having an invo-
lute groove a passing around them, which is depended at a², in order to allow
the largest part of the cone to pass freely through between them. In Figure 4
the taper pologonal casting b is shewn as suspended by a chain c, which may
be connected to a counterbalance weight in any convenient way. If the rolls
are moved in the direction indicated by arrows, the casting will be uniformly
acted upon as is descends, the resceding surfaces of the involute grooves allowing
the thicker part of the metal pass between them. As soon as the rolls assume
the position shewn in Figure 6, the block of metal 6 may be moved upwards
by the workman pulling down the counterbalance; the piece of metal b should
then be turned partly round and again lowered between the rolls. I prefer to
use slow motion in rolling large masses in this manner, in order that the
workman may the more readily keep time with the movement of the rolls,
the large mass retaining its heat for a sufficient time to enable him to do so.
The second rolling mill, herein-before referred to, consists of three rolls,
arranged in the following manner :-Two of them are placed side by side with
their axes in the same horizontal plane, and the third roller is to be placed
above and between them, in a similar manner to the arrangement of rollers
employed in the mills used for crushing sugar canes; the rollers, however, are
not cylinder, but are cones of the same proportions as the casting number 1,
before referred to. The three rollers should be mounted in a strong frame,
and be provided with screws, for the purpose of adjusting their relative position
to each other. The conical gun casting having been heated to a full red heat
is placed in between the three rollers, which are then put in motion, the screws
being tightened up and the rolling continued until the desired amount of com-
pression of the metal has been effected. When it is intended to perform a
like process on the gun casting No. 3, the rolls have mouldings or grooves
formed around them, corresponding with the raised mouldings to be formed on
the gun, and thus a due compression of the whole may take place, the rolled
surface giving all the external finish that is necessary except at the ends, which

page_text: may be finished in the lathe. In some cases it may be found preferable to
cast the gun hollow, in which case a hard mandril should be put into the gun
while being operated upon between the rollers. When not cast hollow, the
boring of the gun may take place in a boring mill as usual, either before or
after the roller process. In some cases it may be found convenient to allow
the bore to extend entirely through the gun, in which case a breech may be
screwed or otherwise fixed into the thick end of the gun. It will be obvious
that in this mode of compressing or rolling ordnance the trunnions cannot be
formed on them as usual; I therefore adopt one of the following methods:-
Firstly, the gun may have a shallow hollow cavity of rather large diameter
formed on either side, at the part where the trunnions are usually situated; I
then form two pieces of steel in such manner as when bolted together they
will embrace loosely the lower side of the gun; these pieces are provided
with lugs and bolts, by which they may be fastened to the gun carriage.
There is to be formed on each piece a raised circular projection, which fits
accurately into the shallow cavities made in the sides of the gun, and which
are to answer the purpose of the usual trunnions. This mode of forming the
trunnions or axes on which the gun moves is represented in side elevation
at Figure 7 of the annexed Drawings, and in end elevation at Figure 8, the
gun being shewn as cut thro' on the centre line of the trunnions. e, e, are
two curved pieces of iron or steel, having a circular boss formed upon them
at e, which fits accurately into a circular recess formed in the enlarged
part of the gun f. The lower part of the pieces e are made straight, and
are secured firmly together by bolts i. There is also a flange at e, by which
the trunnion pieces are bolted to the woodden cheeks of the gun carriage.
Secondly, I bore a hole in the breech end of the gun at right angles to its
length, and as far back as will not weaken the gun; through this hole I press
a stout steel pin. The ends of the pin are fitted into the eyes of two wrought
iron or steel tension bars, which are sufficiently long to reach that part of the
gun where the trunnions are usually placed, where the tension bars are to be
jointed to a piece of wrought iron or steel, having a central hollow, in which
the gun rests.
carriage.
This piece of steel is to be secured by bolts to the gun
In order that this part of my said Invention may be fully understood, I
have shown on the annexed Sheet of Drawings an end elevation thereof at
Figure 9, a side elevation at Figure 10, and a plan at Figure 11. m is a
piece of ordnance without any trunnions formed thereon; the breech end has
formed upon it a stout cylindrical projection m*, through which a steel pin n
passes. This pin passes through the eye of two tension bars P.Pi the opposite

page_text: end of these bars which reach to that part of that gun to have the trunnions
are usually situated, and are there jointed to a strong piece of iron or steel 7,
which is provided with lugs r*, between which the ends of the bars p, p, are
fitted, and through which the steel pins s pass. The piece of metal is curved
so as to pass under the gun, and this part is also rounded, as shown by dots
at r', in Figure 10. There are also flanges formed at r², by means of which
it is firmly bolted to the carriage frame t. The gun m resting on the curved
part r will be free to move up or down as if it were provided with trunnions
in the usual way, while the tension bars p will prevent any backward move-
ment from taking place without the carriage moving with it.
And, thirdly, in some cases I form at the part where the trunnions are
usually situated a raised band around the gun. This band is of a spherical
form, to which I adapt a kind of plumber block, opening in two halves, the
lower one being secured by bolts to the gun carriage, and the upper half
secured by bolts to the lower one. This substitute for the trunnion admits of
anniversal motion of the gun within given limits. This mode of forming
a substitute for the ordinary trunnion is represented at Figure 12 of the
annexed Sheet of Drawings, which shews a gun with the spherical pro-
jection enclosed between the halves of the clip v, which are fitted truly
to the spherical part of the gun; the lower half is provided with flanges, by
means of which it may be secured to the gun carriage w. The muzzle of the
gun may either be hollowed out to reduce the pressure at the point of exit, as
shown in section at Figure 14, or it may be turned down a little, and a suitable
ring shrunk on it, and secured by rivetting down; the metal of the end of the
breech end may be finished in the lathe, and the whole exterior may be either
turned, or, in the case of the polygonal gun, finished in the plaining machine.
The manner of fitting on the muzzle ring will be understood by reference to
Figure 15, which shows a section of part of a gun a, with the ring y shrunk
and rivetted thereon. The great cohesive strength of cast malleable iron or
steel, as compared with ordinary cast iron, admits of a heavier projectile being
used than is usual with guns as at present constructed; but as the generality
of elongated projectiles are greatly obstructed by the atmosphere, and turned
more or less from their intended direction, unless, they are caused to move with
their longer axis in the line of flight, I therefore give such a figure to the
projectile as will cause it to suffer very little deviation or increase.its.resistance
from the air, and which from its increased weight will be formed of great
service when battering of a short range. The same figure will also give a
corresponding increase in weight to the charge contained in shells. This
form of projectile would be simply a perfect sphere, of a size too large for the

page_text: gun, but for the exception of a flat or cylindrical zone made around, which
it fits accurately the bore of gun. The proportion I recommend is about
a seven-inch sphere for a six-inch gun, which will increase the weight con-
siderably, and at the same time the extreme deviation from a true sphere will
not exceed half an inch at any part. The centre of gravity of such a shot
will be the centre of the large curved surface, and by revolving on this centre
the greater part of it will present to the air the same motion as a common
spherical shot. A projectile of this form is represented at Figure 17 of the
annexed Sheet of. Drawing. z is a flat zone, which is made to fit accurately
to the gun. However, where both a heavier shot and a longer range are
required, I form a hollow cast-steel ball, which may be stamped while red hot
bettween dies, and be thus compressed, and its power of cohesion increased.
This ball I fill with molten lead, the increased specific gravity of which will
both increase its weight and range; both of which modes of increasing the
ordinary weight of the projectile may be safely employed with guns manu-
factured in a manner herein-before described. A section, of a shot or
projectile, having its interior filled with lead or other dense metal, is shown.
in section at Figure 16 of the annexed Sheet of Drawings; the part A
representing the steel shell, and the part B indicating the lead or other
heavy metal.
Having thus described my Invention, and the manner in which the same is.
to be carried into effect, I desire it to be understood that I do not confine
myself to the precise details herein described in carrying out my said Invention
into operation, provided that the peculiar features which characterize my said
Invention or some of them be retained; but what I do claim is,―
Firstly, the casting or founding of ordnance in malleable steel obtained by
the partial decarbonization of crude or refined iron.
Secondly, I claim casting or founding ordnance in molten malleable iron.
Thirdly, I claim rolling conical masses of cast metal to be used in making
ordnance.
Fourthly, I claim forming a cavity on each side of a gun or other piece of
ordnance, and fitting thereto suitable pieces of metal so as to form an axis or
trunnion, as herein described.
Fifthly, I claim the use of jointed tension bars in lieu of trunnion: when
applied to ordnance in the manner herein described.
Sixthly, I claim the use of spherical trunnions, as herein described..
Seventhly, I claim forming a flat or cylindrical zone around a spherical.
projectile, so as to enable such projectele to be used in ordnance having a bore
smaller than the said sphere.

page_text: Lastly, I claim the combined use of steel and lead in making projectiles, as
herein described.
In witness whereof, I, the said Henry Bessemer, have hereunto set my
hand and seal, this Seventeenth day of April, in the year of our Lord
One thousand eight hundred and fifty-six.
Witness,
B. GOBEY,
4 Old Square, Lincoln's Inn.
HENRY BESSEMER. (L.s.)