A.D. 1859, 30th July. N° 1769.
(This Invention received Provisional Protection only.)
PROVISIONAL SPECIFICATION left by the said Thomas Firth at the Office of the Commissioners of Patents, with his Petition, on the 30th July 1859.
I, THOMAS FIRTH, of Sheffield, in the County of York, Iron and Steel Manufacturer, do hereby declare the nature of the said Invention for “An IMPROVED BREECH-LOADING CANNON,” to be as follows:—
This Invention is applicable to either smooth bored or riffled cannon, and may be used for either field battery, or marine purposes. In the breech end of the gun a horizontal slot is formed, and in this slot revolves a breech piece mounted on a strong vertical pin, and containing several chambers placed in a radial direction. It is preferred to employ four chambers formed at right angles to each other, each furnished with a separate touch-hole. The breech piece is caused to revolve (when required) by means of a lever which works loosely upon the center pin, each of such teeth or projections of a crown ratchet wheel fixed on the pin, each of such teeth or projections corresponding with one of the chambers. There is a stop which, when the lever is brought against it, indicates that one of the chambers is precisely in a line with the barrel. The mouth of each chamber and the breech end of the barrel are turned cylindrical and of the same diameter, and a collar is fitted on the barrel, which before firing is slidden partly over the mouth of the chamber, and thus makes the joint between the barrel and chamber perfect and secure. Firth’s Improved Breech-loading Cannon. This collar must, of course, be moved off the mouth of the chamber after firing, before the breech piece can be revolved. This gun is to be mounted on a suitable carriage, so constructed and arranged as to allow of its being elevated and depressed, and pointed laterally within a range of about forty-five degrees. The gun can be worked very rapidly by three persons; the first loading the chambers at one side, the second revolving the breech piece and firing, and the third sponging the discharged chambers at the other side.