The general characteristics of the European rifles, up to 1850, are a very large calibre, a comparatively light short barrel, with a quick twist, _i.e._, about one turn in three feet, sometimes using a patch, and sometimes not, the bullet circular, and its front part flattened by starting and ramming down. ~American alterations.~ It appears that the introduction of additional weight in the barrel, reduction in the size of the calibre, the constant use of the patch, a slower twist, generally one turn in 6ft., combined with (what is now known to be a detriment) great length of barrel, are exclusively American. ~Picket bullet.~ A round ended picket (plate 20, fig. 16), was occasionally used in some parts of the States, until the invention of Mr. Allen Clarke, of the flat ended picket, which allows a much greater charge of powder, producing greater velocity, and consequently less variation in a side wind. ~On the comparative merits of rifles.~ ~Points in a perfect rifle.~ A rifle may perform first rate at short ranges, and fail entirely at long, while a rifle which will fire well at extreme ranges can never fail of good shooting at short. In fact certain calibres, &c., &c., &c., perform best at certain distances, and in the combinations of a perfect rifle there are certain points to be attended to, or the weapon will be deficient and inferior. ~Velocity.~ It is desirable to give a bullet as much velocity as it can safely be started with, and the limit is the recoil of the gun, and the liability of the bullets to be upset or destroyed, for as soon as this upsetting takes place, the performance becomes inferior, and the circle of error enlarged. ~Degree of twist.~ It is clear that a bullet projected with sufficient twist to keep it steady in boisterous and windy weather, must of necessity have more twist than is actually necessary in a still favourable time; hence a rifle for general purposes, should always have too much twist rather than too little. ~Weight of bullet.~