it affords protection, admits the circulation of air necessary in working the guns. Small sliding iron hatchways are also provided, to afford an entrance for the men through this portion.
The turret is constructed for two heavy guns, which constitute the whole armament of the battery. They are placed precisely parallel with each other, and both are directed out the same side of the turret. Those selected for the first trial were 11-inch Dahlgren smooth-bore guns, carrying 168 lb. round shot. Some wrought-iron shot were provided for the first encounter, but their use was forbidden for fear of their bursting the guns, by reason of their weight, being 15 lbs. greater than that of the shot used in proving the guns. The port-holes are circular openings, 3 feet above the deck, just large enough to admit the muzzle of the gun, and kept closed by a sliding shutter, managed on the inside, and removed only when the gun is run out to be fired. The gun-carriages are of wrought iron and run on slides very accurately constructed. The sighting of the guns was designed to be not over their line through the port-holes; but four holes were pierced through the turret at the height of the eye for telescopes, and just outside of the holes reflectors were fixed, which bent the ray of light coming in a direction parallel with the guns through the axis of the telescope. In action, however, the ordinary mode of sighting was adopted.
The turret is caused to revolve to the right or left, by the movement of a small wheel which controls the action of the steam, and is turned by the gunner or his assistants, and a scale is provided by which the elevation of the guns is also adjusted. When ready for firing, the shutter is triced up by the gunner, the piece is run out, fired, and instantly returns by the recoil, a friction clamp upon the sides of the ways arresting it at any desired point. On this side of the turret is an additional thickness of iron plating of sbout 3 inches.
The pilot or wheel-house, as originally constructed, was a square box formed of bars or beams of wrought iron, 9 inches by 12, interlocked at the corners, and covered with heavy plating. Elongated horizontal apertures at the sides afford the only look-out for the helmsman. These apertures may also be
