The Birmingham age-herald., 1905-10-29
NAVAL ORDNANCE.
Changes That Have Come In Guns
 Since the Civil War.

From the Scientific American.
 Naval ordnance has made greater strides in the forty years that have intervened since the civil war than in several cen- turies preceding.
 The heaviest piece carried in the civil war was the fifteen inch smooth bore. This gun weighed 42,o00 pounds. its length over all was 15 feet inch, it's maximum diameter at the breech was four feet and with an ordinary charge of thirty-five pounds of black cannon powder it fired a spherical shell weighing $50 pounds. Ac- cording to the ordnance regulations, un- der extraordinary conditions these guns might be fired twenty rounds "at ironclads at close quarters using 100 pounds of hexagonal or cubical powder and solid shot weighing 450 pounds. Under these conditions the respectable muzzle velocity of 1900 foot seconds was obtained, with corresponding muzzle energy of 7sg7 foot tons.
 Now compare these results with the most powerful gun in our navy today namely, the twelve inch 45 caliber rifle, which weighs 53.4 tons. has total length of 45 feet and with a charge of 360 pounds of smokeless powder, fires an $50 pound shell with muzzle velocity of 2So0 foot seconds and muzzie energy of 46.246 foot tons The true basis of comparison of the relative deficiencies of the two guns IS the amount of energy developed per ton of the weight of the gun, and on this basis we find that the old fifteen inch smooth bore gun when fired with 100 pounds of powder developed 427 foot tons of energy per ton of gun as against SIP foot tons of energy per ton devolped by the modern twelve inch gun.
 If we take account of the durability of the gun the advantage will be strongly on the side of the modern piece, for whereas the fifteen inch smooth bore was limited to twenty rounds under the given conditions the modern twelve inch rifles, judging from the small amount of erosion developed with nitrocelulose powders should have a usual life of at least half thousand rounds. Moreover 1t must be remembered that the modern elongated shell will hold its velocity much longer than the old spherical shell of the smooth bore, and consequently the respective muzzle velocities and energies are not an exact criterion of efficiency
 The gun of 1862 that answers to the modern secondary battery six inch rifle is the Parrott muzzle loading rifle cast iron gun which was strengthened at the breech over the powder chamber by shrinking thereon an iron hoop. The bore of the gun was GA inches. It weighed 43o tons, was F feet inches in length ana with charge of ten pounds of powder 1t fired 100 pound shell with an initial velocity of 10S0 foot seconds and a muzzle energy of S10 foot tons.
 Compare this with the modern six inch rifle. which weighs S.5 tons. is % feet in length and with charge of forty pounds of smokeless powder fires 100 pound shell with an initial velocity of 29O0 feet per second and an initial energy of 5s3s foot tons. Compared on the basis of energy per ton of gun. we find that the 100 pounder Parrott muzzle loader devel- oped 1S6 foot tons of energy per ton of gun, whereas the modern six inch breech- loading rifle deyelopes 7S4ls foot tons of energy per ton of gun. etsr, i.s