Improvements in Revolver Fire-arms.
Year: 1894

page_text: PROVISIONAL SPECIFICATION.
Improvements in Revolver Fire-arms.
We, JOHN FRANCIS LATHAM of 27 Pall Mall in the County of Middlesex,
Sword Manufacturer, and HENRY WILKINSON LATHAM of 30 Priory Road,
Chiswick, in the County of Middlesex, Engineer, do hereby declare the nature of
this invention to be as follows:-
This invention relates to breech-loading revolving fire-arms and has reference
particularly to the means for locking the barrel in its closed position and for
retaining the cylinder in position against the action of the extractor spring.
In carrying the first part of our invention into practice we provide two ears or
lugs projecting upwards from the upper part of the body where the extension of the
top rib of the barrel meets it; this extension overhangs the cylinder in the usual
manner. The front faces of these lugs are preferably vertical and the back faces
curved concentrically with the pivot by which the barrel is hinged to the body.
Between the lugs is a gap or recess into which when the fire-arm is closed, a
narrowed portion of the top-rib-extension fits, which latter at its end behind this
narrowed portion widens out to the over-all width of the lugs. This part of the
top-rib-extension forms as it were a T the stem fitting between and the head behind
the two lugs the inner faces of the head being curved to match the curves upon the
back faces of the lugs before described. By these means we provide a device for
securing the barrel against all except rotary movement on the body, which latter
movement is necessary for the opening and closing of the breech.
To secure the weapon when firing, we may employ one or two hooks each
engaging with a lug or projection on the top-rib-extension, that is to say on the
well-known "Trauter" principle; when two hooks and lugs are used the hooks
may be connected together at the back by a bridge or plate through which is
formed a hole or recess to allow the striker to pass. Or, a fastener of the strap or
stirrup type may be employed, that is to say, a strap pivotted to the body and
passing over the top-rib-extension so as to hold it firmly in place. This strap is
preferably extended beyond its pivot at one or both sides and is provided with one
or two thumb pieces, by operating which the strap may be swung backwards clear
of the top-rib-extension to admit of the breech being opened. The strap may be
provided with a back plate having a hole or recess to allow the striker to pass
through.
In carrying the second part of our invention into practice we not only fulfil the
function previously mentioned but also another important function viz.: the
prevention of the cylinder, when only partially filled with loaded cartridges, and
when the breech is opened, from being rotated under the weight of the loaded
cartridges; the want of a device for fulfilling this last named function frequently
causes an empty cartridge chamber to be presented to the barrel. For attaining
these objects we provide a spring-catch preferably secured in a recess in the under-
side of the top-rib-extension, and the projecting portion or catch proper of which
engages the rear end of the cylinder, when the breech is open. The spring-catch
is sufficiently long to enable it when the breech is closed to engage with the bottom
of the before-mentioned gap or recess of the body, the catch being thereby moved
out of engagement with the cylinder.

page_text: When the weapon is being opened and before the extractor lifter has time to operate,
the spring-catch falls upon and engages the end of the cylinder thus preventing the
latter from leaving its spindle and at the same time bearing on the cylinder
with sufficient pressure to prevent it from being rotated by the weight of loaded
cartridges.
By pressing the spring-catch into the recess in the top-rib-extension when the
breech is open the cylinder may be readily removed or replaced.
Dated this 20th day of November 1894.
BOULT & WADE,
Agents for the Applicants.
We, JOHN FRANCIS LATHAM of 27 Pall Mall, in the County of Middlesex,
Sword Manufacturer, and HENRY WILKINSON LATHAM of 30 Priory Road,
Chiswick, in the County of Middlesex, Engineer, do hereby declare the nature of
this invention, and in what manner the same is to be performed, to be particularly
described and ascertained in and by the following statement :-
This invention relates to breech-loading revolving fire-arms and has reference
particularly to the means for locking the barrel in its closed position and for
retaining the cylinder in position against the action of the extractor spring.
The invention will be best understood by reference to the accompanying
drawings in which
Fig. 1 is a side elevation of portion of a revolver with our improvements applied
thereto, the breech in this view being closed;
Fig. 2 is a view similar to Fig. 1 with the breech open.
Fig. 3 is a side elevation and Fig. 4 an underside view of the top-rib extension
and spring-catch for retaining the cylinder in position.
and
Fig. 5 is a perspective view of the stirrup-fastener.
Fig. 6 is a section showing the stirrup fastener applied to the standing breech
Fig. 7 a plan of portion of the standing breech.
Like letters indicate like parts throughout the drawings.
In carrying the first part of our invention into practice we provide two ears or
lugs A projecting upwards from the standing breech or upper part of the body A
where the extension B¹ of the top rib of the barrel B meets it; this extension B₁
overhangs the cylinder C in the usual manner. The front faces a of these lugs A¹
are preferably vertical and the back faces a¹ as shown in Fig. 6, curved
concentrically with the pivot D by which the barrel B is hinged to the body A.
Between the lugs A¹ is a gap or recess A 2 Figs. 6 and 7 into which, when the
fire-arm is closed, a narrowed portion or neck B2 of the top-rib-extension B₁ fits,
which latter, at its end behind this narrowed portion, widens out into a head B 3 of
the over-all width of the lugs A¹. This part B2 B3 of the top-rib-extension B₁
as shown clearly in Fig. 4 forms as it were a T the stem B2 fitting between and
the head B3 behind the two Ings A¹ the inner faces 6 of the head B3 being
curved to match the curves of the back faces a¹ of the lugs A¹. By these means
we provide a device for securing the barrel Bagainst all except rotary movement on
the body, which latter movement is necessary for the opening and closing of the
breech as shown in Figs. 1 and 2.
To secure the weapon when firing, we may employ one or two hooks each
engaging with a lug or projection on the top-rib-extension, that is to say on the
well-known "Tranter" principle; when two hooks and lugs are used the hooks

page_text: may be connected together at the back by a bridge or plate through which is
formed a hole or recess to allow the striker to pass. Or, as shown in the drawings,
particularly Fig. 5, a fastener E of the strap or stirrup type may be employed,
that is to say, a strap pivoted as at E' to the body A and pressed by a spring F
over the top-rib-extension B' so as to hold it firmly in place. This strap E is
preferably extended beyond its pivot at one or both sides and is provided with one
or two thumb pieces E 2, by operating which the strap against the influence of the
spring F may be swung backwards clear of the top-rib-extension to admit of the
breech being opened. The strap may be provided with a back plate having a hole
or recess to allow the striker G to pass through.
In carrying the second part of our invention into practice we not only fulfil the
function previously mentioned but also another important function viz.; the
prevention of the cylinder C, when only partially filled with loaded cartridges,
and when the breech is opened, from being rotated under the weight of the loaded
cartiidges; the want of a device for fulfilling this last nained function frequently
For attaining
causes an empty cartridge chamber to be presented to the barrel.
these objects we provide a spring catch H preferably secured as by a screw H' in a
recess B4 in the underside of the top-rib-extension B₁, and the projecting portion or
catch proper H 2 of which engages the rear end of the cylinder C, when the breech
is open. The spring-catch H is sufficiently long to enable it, when the breech is
closed, to engage with the bottom of the before-mentioned gap or
recess A 2
of the body A, the catch being thereby moved out of engagement with the
cylinder.
When the weapon is being opened and before the extractor lifter has time to
operate, the spring-catch H falls upon and engages the end of the cylinder C thus
preventing the latter from leaving its spindle and at the same time bearing on the
cylinder with sufficient pressure to prevent it from being rotated by the weight of
loaded cartridges.
By pressing the spring-catch H into the recess B4 in the top-rib-extension, when
the breech is open, the cylinder C may be readily removed or replaced.
If desired, we may construct the spring H without the catch H 2 in which case
it will act merely as a brake to prevent the too-free rotation of the cylinder when
the weapon is opened, any suitable catch independent of the spring H being under
that construction provided to retain the cylinder on its spindle.
Having now particularly described and ascertained the nature of the said inven-
tion, and in what manner the same is to be performed, we declare that what we
claim is ;-
1. In a revolving fire-arm the combination with a T-head such as B2 B3 on the
barrel extension B₁ of lugs such as A¹ and a recess A 2 on the standing breech or
body for receiving or engaging with the T-head substantially as described and
illustrated in the accompanying drawings.
2. In a revolving fire-arm a device for locking the barrel comprising a T-head
such as B2 B3 on the barrel extension lugs such as A' and a recess A 2 on the
standing breech or bcdy and a spring-controlled strap or fastener such as E E2
pivoted to the body substantially as described and illustrated in the accompanying
drawings.
3. In a revolving fire-arm the combination with the barrel extension B' and
cylinder of a spring-catch such as H H 2 secured to the barrel extension B¹ and
adapted to engage with and bear upon the cylinder substantially as described
and illustrated in the accompanying drawings.
4. In a revolving fire-arin the combination with the barrel extension B¹ and
cylinder C of a spring or brake device adapted to bear on the cylinder when the
weapon is opened and be released from it when the weapon is closed substantially
as described.
5. In a revolving fire-arm the combination and arrangement of parts constituting

page_text: the complete barrel-locking and cylinder-retaining devices substantially as described
and illustrated in the accompanying drawings.
Dated this 16th day of August 1895.
JOHN F. LATHAM.
H. WILKINSON LATHAM.
Boult & Wade,
Agents for the Applicants.