The failure of the Americans to produce during the great war a practical breech-loading field-gun is doubtless due to the fact that the field artillery in use at that time answered fully all the requirements then existing. Owing to the nature of the country in which the armies were operating, the range of the 3-inch rifled gun was fully as great as could have been desired; and on the broken and wooded ground which generally formed our field of battle, the smooth-bore Napoleon gun, firing shrapnel and canister, seemed to have reached almost the acme of destructiveness. Moreover, the muzzle-loading cannon, both rifled and smooth-bore, were served with such celerity as to make it a matter of doubt for some years after whether the introduction of breech-loading field-guns would materially increase the rapidity of fire. It was not until infantry fire had greatly increased in range and rapidity that a further improvement in field artillery became necessary. In siege artillery, heavy rifled guns of the Rodman and the Parrott type appeared. The Parrott gun was of cast iron, strengthened by shrinking a coiled band of wrought iron over the portion of the piece surrounding the charge. The famous “Swamp Angel,” used in the siege of Charleston, was a Parrott gun. The sea-coast artillery consisted mainly of smooth-bores of large calibre, which were able to contend successfully with any armor then afloat. It is a curious fact that the war, so to speak, between guns and armor has been incessantly waged since the introduction of the latter, every advance of armor towards the degree of invulnerability being met with the production of a gun capable of piercing it. The sea-coast artillery of the United States in the Civil War met fully every demand to which it was subjected.