IMPROVEMENTS IN REVOLVING BATTERY GUNS
Year: 1871

page_text: LETTERS PATENT to Alexander Melville Clark, of 53, Chancery Lano,
in the County of Middlesex, Patent Agent, for the Invention of
"IMPROVEMENTS IN REVOLVING BATTERY GUNS."-A communication from
abroad by Richard Jordan Gatling, of Hartford, County of Hartford,
and State of Connecticut, United States of America.
Scaled the 19th December 1871, and dated the 3rd November 1871.
COMPLETE SPECIFICATION filed by the said Alexander Melville Clark
at the Office of the Commissioners of Patents, with his Petition and
Declaration, on the 3rd November 1871, pursuant to the 9th Section
of the Patent Law Amendment Act, 1852.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, ALEXANDER
MELVILLE CLARK, of 53, Chancery Lane, in the County of Middlesex,
Patent Agent, send greeting.
WHEREAS I am in possession of an Invention for "IMPROVEMENTS
IN REVOLVING BATTERY GUNS," and have petitioned Her Majesty to grant
unto me, my executors, administrators, and assigns, Her Royal Letters

page_text: Patent for the same, and have made solemn Declaration that it has
been communicated to me from abroad by Richard Jordan Gatling,
of Hartford, County of Hartford, and State of Connecticut, United
States of America.
NOW KNOW YE, that I, the said Alexander Melville Clark, do hereby
declare that the following Complete Specification, under my hand and
scal, fully describes and ascertains the nature of the said Invention, and
in what manner the same is to be performed, in and by the following
statement, reference being had to the three Sheets of Drawings here-
unto annexed, and to the letters and figures marked thereon (that is to 1
say) :-
This Invention relates to several improvements by the original
Inventor of the well-known Gatling gun, which has formed the subject
of Letters Patent of the United Kingdom, granted to Richard Jordan
Gatling, dated 21st March 1865, No. 790, and to Alexander Melville:
Clark, dated 19th November 1869, No. 3341.
The object of the present Invention is principally to reduce the length.
of lock and consequent length of breech case, and thereby diminish the
weight, expense, and difficulty of manufacture of the entire gun. This
object is attained to a great extent by doing away with the cocking
cam formerly employed, and substituting therefor a detaining cam
which takes hold of the knob at the rear end of the lock hammer of
firing pin that serves as a lock hammer, and holds it in the same vertical
plane while the lock is moving forward. The forward motion of the
lock towards the barrel is thus utilized for cocking in such manner that
the lock hammer or firing pin is held back in the place occupied by
the lock itself in its backward position. The construction of the lock
itself is modified in conformity with the afore-mentioned mechanism,
by providing the lock hammer with an interior shoulder for the spring
to bear against, and with a knob at the outer rear end for the grip
of the detaining cam.
This Invention also consists in an improved construction of the
breech case lock cylinder and also of the carrier block with the view of
preparing the same for the reception of the improved locks, the carrier
block being made hollow to reduce weight and cost of material,
The Invention also consists in applying to the cover of the carrier
block a pendant blade whereby the empty cartridge shells are absolutely

page_text: disengaged from the block and prevented from being carried up with and
by the same, and from interfering with the proper operation of the gun.
The Invention also consists in the use and new arrangement of a
peculiar universal tripod for supporting the gun and allowing its adjust-
ment in every direction.
In the accompanying Drawings, Figure 1 represents a longitudinal
section of the breech part of the gun, showing the improved arrange-
ment of parts; Figure 2 is a longitudinal section of the lock; Figures 3
and 4 are transverse sections of the same on the lines c-c, and c-k,
Figure 2, respectively; Figure 5 is a detail sido view of the lock
hammer or firing pin; Figure 6 is a transverse section, and Figure 7 an
end view of the head which is screwed upon the lock hammer or firing
pin; Figure 8 is an end view of the breech case looking in at the front
end when the lock cylinder and appendages are removed; Figures 9
and 10 are longitudinal sections of the same on the line k-c, Figure 8,
the eye looking in the direction of the arrows 1 and 2 respectively;
Figure 11 is a detail transverse section on the line k-k, Figure 8,.
showing how the lock hammer or firing pin is held back in the detaining
cam; Figure 12 is a vertical transverse section of the lock cylinder
and breech case, the line c-q, in Figures 1 and 9 indicating the plane
of section; Figure 13 is a vertical transverse section of the carrier block,.
the line q-q, in Figure 1 indicating the plane of section; Figure 14 is a
transverse section, showing the hinged covering plate G and pendant
blade y; Figure 15 is a transverse section of the frame which supports
the forked swivel pin for making the gun play horizontally by the aid
of double threaded screw m³, the line k-q, Figure 8, indicating the plane
of section; Figure 16 is a horizontal section of the same on the line q—k,
Figure 15; Figure 17 is a bottom view of the cover over the carrier
block of the gun; Figure 18 is a top view of the same; Figure 19 is a
side elevation of the entire gun, showing it mounted upon a tripod;
Figure 20 is a side elevation of the gun mounted on a field carriage, one
wheel being removed to shew the parts more clearly. Similar letters of
reference indicate corresponding parts..
A in the Drawing represents the cylindrical breech case secured upon
the frame of the gun, which is mounted in suitable manner either
upon a gun carriage, tripod, or other suitable support. In this breech
case is the diaphragm a and cascabel plate b, between which a chamber
for the reception of the worm and worm wheel is formed. B is the axial

page_text: block D, and the lock cylinder E, which revolve with it whenever it is
turned by means of the crank handle d, which imparts motion to the
worm. F, F, are the locks, and G is the hopper plate or cover of the
carrier block with an aperture through which the cartridges are supplied
to the latter.
Within the breech case are arranged the stationary spiral or inclined
cams e and f for drawing the locks back and forth; these cam grooves
or tracks are formed on a cylindrical shell H, which is fitted within the
breech case and secured thereto by a longitudinal screw that passes
through the diaphragm a. By means of this screw the shell II with its
cams is held securely to its place. c is the cam groove or track whereon
the locks are forced forward; its front end is by a non-spiral portion g
joined to the front end of the retracting cam f. Directly behind the
junction of e and g is arranged the detaining cam I. The same is a
curved plate having a dovetail shank h, which enters a corresponding
A spring j
slot in an inwardly projecting car or block i of the shell II.
placed between the diaphragm a and shank h serves to force the
detaining cam forward so that the upper end of its curved face will
come against the cam e, but permits the same to move backwards for
purposes herein-after specified. The face of the detaining cam I has
a countersunk groove of such cross section as most conveniently to
receive the knob at the rear end of the lock hammer or firing pin, as
indicated in Figure 11. Each lock F consists of a shell and lock ham-
mer or firing pin mas principal parts. The lock hammer has the firing
pin formed at its front end, as is clearly shown in Figure 5, and a knob n
at its back end, said knob being intended to fit the countersunk groove
of the detaining cam. A spiral spring is placed within the shell, and
around the lock hammer between a shoulder or head o on the latter
and a screw plug p at the back end of the shell. The head o is screwed
upon the lock hammer or firing pin, and is by the spiral spring held
against the front end of the chamber in the shell. If the knob n is taken
hold of and drawn back the spring will be contracted to violently propel
the firing pin forward whenever the knob is released. is the cartridge
shell extractor applied to the lock, and 8 the projecting lug on the lock
that moves along the cams e, f, and thereby causes the forward and
backward motion of the lock; is a dovetail tenon on the lock shell,

page_text: fitting into corresponding grooves of the lock cylinder and carrier block,
as indicated in Figures 12 and 13. The carrier block as well as the
lock cylinder it will be seen are cast or formed hollow with supporting
discs or arms that hold them to the shaft. Considerable weight and
material are thereby economized. From the front end of the lock
cylinder projects a flange a perforated to admit the locks, and made
circular at the outer edge to fit and support the front end of the breech
case. The locks when held by the grooved lock cylinder are with their
projecting lug 8, 8, in such contact with the cams, tracks, or grooves c,f,
respectively, that they will when revolved by the rotation of the lock
cylinder be also moved forwards and backwards in the requisite manner.
to push the cartridges into the barrels, explode the charges, and with-
draw the cartridge shells, substantially as specified in the former Letters
Patent referred to above.
When a lock approaches along a cam e its foremost position the
knob of its lock hammer enters the upper end of the groove in the
detaining cam I. This cam is so held against e and bevelled at its upper
end that the knob most conveniently enters its groove. As the lock
continues to advance, the cam I however detaining the knob n in the
same vertical plane, it is evident that the firing pin will be automatically
drawn back within the lock and the spring contracted; thus the lock
is cocked. As soon as the lock arrives in line with the inner or lower
end of the cam I it is released by the latter, and the lock hammer and
firing pin are propelled forward to explode the charge. In this manner
the charges of the barrels are fired with the utmost precision and regu-
larity. The cam I may if desired be continued more or less far around
at such a distance from the tracks e, f, as to hold the point of the firing
pin slightly drawn in except when in the act of firing. When the shaft
is turned in the opposite working direction the knob will strike the face
of the cam I and push it back against the spring j, the detaining cam
being thereby prevented from cocking. The plate or face g braces the
back ends of the locks at the moment of firing and takes their recoil,
being made strong and larger for this purpose, as shown.
The arrangement of the automatic detaining cam in place of the
cocking apparatus formerly in use is of great advantage. It permits
the dispensing of half the length of lock and breech case, and consequent
reduction of expense and increase of carrying facility. It is not in the
way of the proper function of the other mechanism, and is positive in its

page_text: action. The cover G, Figure 14, is at to hinged to the frame J of the
gun; its other end is by a spring catch x locked to the breech case.
From the under side of the cover projects towards the ascending side of
the carrier block downwardly a blade or plug y which sweeps any
empty cartridge shells that may have remained in the grooves of the
carrier out, and preserves said grooves therefore free to receive new
cartridges for firing at the appropriate place. The crank handle shaft,
Figure 8, carries at its end a screw m² with double (that is to say) right|
and left hand thread, the threads where they unite being cut away to
come to a point, as clearly shown in Figure 8, but which forms no part
of the present Invention. This screw, which is only employed when the
gun is mounted upon a gun carriage, as in Figure 20, works in con-
nection with a forked pin N, which is swivelled in a transverse slide or
frame M that is connected by a long socket with the ball or head of
tail screw of the carriage, as shown, thus forming a kind of ball-and-
socket joint to permit of the frame M adapting itself freely to the
movements of the gun. When the shaft is turned the thread of the
screw m² will gradually work along one face of the fork N, and thereby
cause the entire gun to swing horizontally in one direction until the
fork N reaches one end of the screw, where it is slightly turned to be in
contact with the reverse thread, which will cause a reversed horizontal
play of the gun under a continued rotation in the same direction of the
shaft. The forked pin N is held up by a clamp screw p³ received in a
rotating collar or socket p³ fitted in frame M in the following manner :-
p' is a spring attached to p³, and bearing against a pin p³ fixed in
frame M, as shown, the office of the spring being to hold p³ and with it
the pin N steady in one position until the latter is turned on arriving
at the end of screw m². The movement of socket 2³ is limited by a
flange on M working in a recess in the periphery of p³, as shewn clearly
in Figure 15.
'
Figure 19 represents the gun mounted upon a tripod O. The legs of
the same are pivoted in a metallic head 13, which has a vertical pro-
jecting pin that is swivelled in a socket &³ of a frame P, in which frame
the trunnions of the frame J have their bearings. The whole gun,
including the frames J and P can swing horizontally on the pin of the
tripod. The tripod will be convenient for mounting the gun on animals.
is the tail screw for regulating the range of the gun. It works in an
arm 3 of the frame P, and has a round head at its upper end which

page_text: plays like a ball and socket in a recessed block provided on the
under side of the barrel case. By means of the tripod the gun can be
supported on every kind of ground, and in suitable position.
For field service it is intended to use the carriage, but in forts, or on
the backs of animals, &c., the tripod will be a more convenient
support and less expensive. It can be entirely folded up for transporta-
tion. When the gun is mounted upon a carriage the frame P constitutes
a substantial part of the carriage, the tail screw to being held in the
latter, as shown.
Having described the nature of the Invention, and the manner of
performing the same, I declare that what I claim as the Invention and
desire to secure by Letters Patent is,―
1st. The detaining cam I, or its equivalent, arranged within the
stationary spiral cam to detain the lock hammer during the forward
motion of the lock and thereby cock the latter, as set forth.
2ndly. The lock cams, tracks, or guides e and g so arranged with
respect to the groove detaining cam I that the latter is behind the
forward portion of e and behind part of g, as specified.
3rdly. The spring j, or its equivalent, applied behind the detaining
cam I to make the same yielding backwardly, as specified.
4thly. The shell H carrying the cams or guides e, f, g, and the
detaining cam I, and secured within the breech case by means of a
screw v, as specified.
5thly. The lock F having a lock hammer m which projects through
the back end of the lock shell and has a knob n at its end, substantially
as and for the purpose herein shown and described.
6thly. A rotary battery gun provided with revolving reciprocating
blocks which are automatically cocked during their forward motion by a
mere detention of the lock hammer and fired by a release of the same,
as specified.
7thly. The carrier block D and lock cylinder E made hollow, sub-
stantially as and for the purpose herein shown and described.
Sthly. The downwardly projecting blade y applied to the under side
of the cover G to remove any adhering cartridge shells from the grooves
of the carrier block, as specified.

page_text: 9thly. The transverse frame or slide M constructed, substantially, as
herein-before shown and described, to support the breech of the gun
in its horizontal training movement to receive the tail screw & and to
hold the forked swivel pin N.
10thly. The moveable socket p³ having a spring p' working in frame M
and provided with a clamp screw to support the pin N, substantially as
and for the purpose shown and described.
11thly. The tripod O applied to a battery gun by being swivelled on a
frame P, substantially as herein shown and described.
12thly. The screw provided with a round head, substantially as
herein shown and described.
In witness whereof, I, the said Alexander Melville Clark, have
hereunto set my hand and seal, this Third day of November,
in the year of our Lord One thousand eight hundred and
seventy-one.