the projectile must rotate with perfect steadiness and precision on its axis. He can increase its length so considerably as to secure space for converting it into a shell if necessary; and, being able to use metal of any degree of hardness, he can adapt its form and strength exactly to the work which it has to perform. Thus with a rifle 39 inches long and half-inch bore, having a turn in 20 inches, or two turns in its length, he finds no difficulty in penetrating a wrought-iron plate 6-10ths of an inch thick or cutting a core out of a piece of solid timber half a foot thick; and some idea may be formed of the extraordinary power of this arm when we mention that his projectiles in their flight rotate at the rate of 15,000 revolutions per minute. The question of driving holes in the 4-inch breast plates of floating batteries is at once solved by the application of these principles to artillery, the construction of which this new rifle proves must be completely revolutionized. A weapon which in expert hands will make good practice at 1,400 yards, and the range of which can be very easily helped by a telescope if necessary, gives the _coup de grace_ to our present system of field batteries. At the Alma it would have silenced the Russian guns or driven them from their position, rendering the rush of the Light Division, with the heavy loss of life consequent thereon, unnecessary. Nor during the siege of Sebastopol would the rope mantlets of the Redan and the Malakhoff having given much protection to the men working behind the embrasures,” &c., &c., &c. So much for the praise bestowed by Mr. Whitworth on his own production. A beautiful experiment it has been, and one for which the scientific world is bound to be thankful; giving, as it does, perhaps a faint idea only of what is yet to be effected. However, all is not gold that glitters: it is very well to do all this by straining every principle that can be brought to bear,--extra charge, bullets hardened and turned with mathematical precision, steel barrels, with a fineness of polish in the interior like that of a looking-glass--these are all great adjuncts in the trial against an ordinary unprepared gun, taken from a number promiscuously, and which perhaps might be the worst specimen in the possession of the party at Hythe. But these are trifles when compared with the two following facts. The diameter of the bore of Mr. Whitworth’s is 500, or half-inch at the largest diameter, and 450 at the smallest, or a mean, taking the two extremes, of fifty bore; the Enfield is 577, or twenty-five bore, and the bullets on leaving the guns were the same weight exactly. The length of the Enfield bullet is 7/8 inch, that of the Whitworth is 1-3/8 inch. But all this will be more fully seen from the woodcuts. [Illustration: ENFIELD BARREL AND PRITCHETT BULLETS.] [Illustration: WHITWORTH BARREL AND BULLETS.]