The annexed engravings are views of im- I provements in breech loading fire-arms invented by Wm. W. Marston, of this city, auc fdr which a patent was granted on the 8th of January (1851,) also the cartridge for such fire arms, invented by Marston amp; Goodell, patented on the 18th of last May (1852.) Figure 1 is a side view of Marston's breech loading rifle ; figure 2 a like view of a breech loading pistol ; figure 3 is an inside view of an improved gun-lock ; figure 4 is an interior view, showing the patent breech ; figure 5 is a side view of the shell of a patent cartridge, and figures 6 and 7 are upright views of two cartridges of different sizes. The same letters refer to like parts. It is a most superior and convenient breech-loading fire-arm, and a very brief description will explain it to any person. A, figure 4, is the butt of the barrel, which is let into and secured in the stock ; B is the breech bolt. It is both ramrod and breech at the same time, and in this consists one of its excellencies. This breech is now pushed close to the butt of the barrel and closes up the orifice of the bore, To load the rifle apply the hand to the lever, G, and push it forward towards the trigger, H. and the breech, which is a sliding bolt, will be drawn back into the end of the dark recess exhibited, and expose the chamber for the reception of the cartridge. The cartridge, figure 6, is simply laid in this chamber (which is then open before, as it is now behind the breech bolt in figure 4,) and the said breech bolt is made to force the cartridge into the bore of the barrel by drawing back the lever, G, into the position shown in all the figures. The rifle or pistol is then loaded, and with a cap on the nipple, is ready to be discharged. This is certainly a very simple mode of loading a rifle or pistol, and can be done nearly in a second of time. The manner in which the breech-bolt is operated and maintained snugly in its place exhibits great skill and ingenuity. The inside of the loading lever, G, is a small arm, E, which forms part of said lever (which works upon the fulcrum or axis, F,) and on its extremity is a cam groove : a pin, C, in the back end of the breech-bolt, B, passes through this groove, therefore, when the said breech-bolt is pressed close up to the ball in the barrel bore, the end of it at C, is in the same position and combination of arrangement, as the keystone of an arch, to receive the backward force of the discharge, in the same manner as pressing upon the apex of the arch. The combination is an ingenious mechanical device and arrangement. A small round part in front of B, fits behind the cartridge and enters the bore of the barrel snugly, so that it is impossible for any leakage of flame or powder to take place. A small hole is drilled through the centre of the breech bolt, which communicates with the priming hole of the cap nipple to ignite the powder in the barrel. This sliding breech bolt along with the loading lever is a very strong arrangement ; no charge of powder can move it in the least. The loading is always uniform without trouble or variation in the result. CARTRIDGES.The cartridge is composed of the shell, 5, in which the conical bullet as shown in figure 6 is placed and cemented and the rest, filled with powder. The butt of the cartridge is a disc of leather with a small hole in its centre, to let the flash of the priming cap pass through the priming hole into the powder. The edges of the leather disc are greased, and the disc of one cartridge is driven out by the bullet of the next cartridge, as the said part of each cartridge is left behind. Every succeeding cartridge, therefore, by driving out the previous leather, cleans out the barrel, so that rifles using such cartridges never require to be swabbed out, the barrel will shine bright inside after firing a thousand shots. LOCK.The lock is of the common, simple, and excellent kind, but as applied to this rifle, it affords the means of strengthening the small three legged brace plate screwed over the tumbler which operates the hammer. M L are the springs abutting on the tumbler, into the the notches, K, of which the trigger latch, I, catches. The two sides of this lock are raised flanges, and thus it differs from the common lock, inasmuch as the springs, amp;c, are contained in it as in a box ; the common lock is let into the stock ; this one has but to be screwed to this stock, which differs from any other. The cartridges are an excellent invention, and the principle of thus loading at the breech is certainly the most simple and best yet presented to us. Rifles, pistols, and shot guns are now manufactured on a large scale, under the eye of the inventor, a practical gunsmith, in the factory on the corner of Washington and Jane streets, this city. No less than 90 hands are employ- ed continually, and rifles from 25 to $100 are constructed. This rifle will no doubt arrest the attention of Mr. J. Chapman, author of '' The American Rifle." The question of good fire-arms has been an exciting one for some time, and at the present moment this rifle of Mr. Marston is creating quite a stir in the capital of France, where Mr. Molton has been astonishing the Parisians with its excellent qualities in rapidity of loading, length of reach, and accuracy of aim. We have no doubt but the breech-loading fire-arm will yet supplant the muzzle loading kind entirely ; why should the ball be rammed down from the top of the barrel to the bottom to be driven back the old road again? It is not reasonable ; no scientific argument can be adduced in its favor, but plenty against it. These rifles can be seen at the store No. 205 Broadway, this city.