CERTAIN IMPROVEMENTS IN FIRE-ARMS AND PROJECTILES
Year: 1855

page_text: PROVISIONAL SPECIFICATION left by Perceval Moses Parsons at the
Office of the Commissioners of Patents, with his Petition, on the
6th March 1855.
I, PERCEVAL MOSES PARSONS, of Duke Street, Adelphi, in the County of
Middlesex, Civil Engineer, do hereby declare the nature of the said Invention
for "CERTAIN IMPROVEMENTS IN FIRE-ARMS AND PROJECTILES" to be as follows:-
Firstly, my Invention consists in making the bore of fire-arms of an improved
shape or form, the section of which would be described by a revolution of a
volute or spiral or similar curve, having its ends joined by a radial line, or by
the partial revolution of two or more such curves, having their adjacent ends
joined by a corresponding number of radial lines; and I obtain the shape or
configuration of the bore by turning a section of this figure on its centre, and
at the same time advancing it forward in a straight line, by which the radial
portion or portions of the section will form a spiral face or faces, against
which a corresponding face or faces in the projectile will be pressed as it is
urged forward in its discharge from the piece, and thereby have a rotatory
motion on its axis imparted to it.
Secondly, my Invention consists in constructing the larger kinds of fire-arms
or ordnance by winding or coiling bands, strips, or bars of wrought iron, steel,
or other wrought metal spirally round a central tube forming the bore of the
gun, or a temporary mandrill, and in forming such bands, strips, or bars of a
taper form, and in rolling them with suitable grooves, tongues, or other recesses

page_text: and projections to connect and hold together the coils; and in rolling or coiling
round sheets or plates of wrought metal, and in placing cylinders or tubes of
wrought metal one within the other, and in uniting the bars, strips, bands,
sheets, plates, cylinders, or tubes by means of a solder, metal, or metallic alloy
which will fuse at a lower temperature than the welding or fusing point of the
wrought metal of which they are composed.
Thirdly, my Invention consists in casting guns or pieces of ordnance with
the bore in them, and giving it a chilled or hardened surface, by the application
of a core having an external surface of iron, steel, or other suitable metal
accurately made to the intended shape of the bore, and in such a manner
that it will collapse by the contraction of the gun or piece of ordnance in
cooling.
Fourthly, my Invention consists in forming projectiles with cross sections,
similar to my improved forms of bore herein-before described under the first
head, so as to present a spiral face to correspond to and fit against the spiral
face of the bore, and acquire a rifle motion thereby; and in constructing them
by encircling the body of the projectile with a coil or coils of sheet or plate
metal, their inner end or ends being firmly attached to it by casting it round
them or otherwise, the outer end or ends being free, so that they will partially
uncoil, thereby expand and fill the bore by the force of the explosion, or by the
pressure of their end or ends against the spiral face or faces of the bore (when
of my improved form) as the projectile is urged forward in its descharge from
the piece.