Range of Columbiad shell guns.
--The furthest range of a hundred-pound shell, even at an elevation of thirty-five degrees given to the gun, is 4,828 yards; the time of flight being thirty-five seconds. The great twelve-inch Columbiad, the largest gun made, loaded with twenty-five pounds of powder, a shell of 172 pounds and the piece at an elevation of thirty-five degrees, has made a range of only 5,409 yards, the projectile occupying thirty-two seconds in its flight, by increasing the elevation to thirty-nine degrees only 100 yards more was gained in the range.
From the same gun, with a charge of powder twenty-eight pounds, a shell of 180 pounds and an elevation of thirty-five degrees, a range of 5,671 yards has been attained, and at an elevation of thirty-nine degrees a range of 5,761 yards (three and a third miles.) which is the greatest that has ever been accomplished by any gun in our service.
The flight occupied thirty-six seconds.
Charleston is, therefore, perfectly safe from the guns of
Fort Sumter.
If it were even within the farthest range of those guns, the angle of elevation necessary to accomplish such a distance is so extreme that to hit the city would be a matter of extreme uncertainty.
The guns of
Fort Sumter can only be raised to an elevation of thirty-three degrees, on account of the casemates, and consequently could do no damage beyond about two miles and a half.
A ten-inch Columbiad, at an elevation of thirty-three degrees, will throw a shell about three miles. There are no such guns in barbette at
Fort Sumter, and if there are any casemate guns of that calibre, no such elevation could be had. The upper surface of the gun would strike against the top of the embrasure at an elevation far short of thirty-three degrees.
