[Footnote 33: It is not to be inferred that the modern _improvements_ (as they are called) are copied from the more ancient _inventions_. Two men of different ages, or even of the same age, sometimes fall upon the same identical discovery, without either's borrowing from the other.] The _materiel_ of artillery employed in modern warfare is divided into two general classes: 1st. _Siege Artillery_, or such as is employed in the attack and defence of places. 2d. _Field Artillery_, or such as is used in battle, or in the field-operations of an army. 1. _Siege Artillery_ is composed of _mortars, large howitzers, Paixhan guns_ or _Columbiads_,[34] and _all cannon_ of _a large calibre._ In our service this class of ordnance includes the twelve, eighteen, twenty-four, thirty-two, and forty-two-pounder guns, the eight, ten, and thirteen-inch mortars, the sixteen-inch stone mortar, the twenty-four-pounder coehorn mortar, the twenty-four-pounder carronade, and the eight, ten, and twelve-inch howitzers. [Footnote 34: These pieces were first invented by Colonel Bomford, of the U.S. army, and used in the war of 1812. The dimensions of these guns were first taken to Europe by a young French officer, and thus fell into the hands of General Paixhan, who immediately introduced them into the French service. They were by this means first made known to the rest of Europe, and received the name of the person who introduced them into the European services, rather than that of the original inventor. All these facts are so fully susceptible of proof, that Europeans now acknowledge themselves indebted to us for the invention; even General Paixhan gives up all claim to originality in his gun, and limits himself to certain improvements which he introduced. The original gun, which was invented by Colonel Bomford, and whose dimensions were carried to General Paixhan in France, is now lying at the ordnance depot, in New York harbor.]