In vessels of this class it is usual to have an open-deck battery, with a poop-deck and top-gallant forecastle at the extremities, but the effort has been made in this type to increase the effectiveness of the battery by giving the guns a more extended lateral train than is possible when a ship is arranged with a forecastle and poop-deck. These, with the accommodations which they provide, have been removed from the ends of the ship, and a superstructure has been erected amidships. This arrangement gives a clear sweep forward and aft for the powerful 8-inch guns, enabling the forward gun to cover an all-around fire of from 40° abaft the beam on the port side to 30° abaft the beam on the starboard side, the after 8-inch gun having a corresponding lateral sweep aft. Within the superstructure are mounted the six 6-inch guns, two on each side on the broadside, with a train of 60° before and abaft the beam, the other two being mounted at diagonally opposite corners in such a way as to admit of their use either on the broadside or for fire ahead or astern. This object is achieved by mounting the two 8-inch guns _en échelon_, the forward gun being on the port side of the centre line of the ship, and the after 8-inch gun on the starboard side of the same line. This is shown on the deck plan.[50] It does not require the discrimination of a professional eye to see the increased power given to the battery by this arrangement. It is an innovation that was very startling to the conservative mind; but the more familiar the idea becomes, the more favorable opinion grows to the change, and the more apparent becomes the increased offensive power of the ship. The extremities of this type of ship will not, of course, be so dry in heavy weather as if it had a forecastle and poop, but it must be remembered that every part of the spar-deck is from nine to ten feet above the water. The rig of the _Atlanta_ is that of a brig, but without head-booms; the fire ahead of the forward guns is thus unobstructed, and the ram with which she is fitted is always clear for use. The division of the hull into water-tight compartments by athwartship bulkheads, and a protective deck over engines and boilers, form a part of the construction. [Illustration: U. S. DESPATCH-BOAT “DOLPHIN.”] The _Dolphin_, though not regarded as a vessel for fighting purposes, is the type of a class that is needed in all navies for duty as a despatch-boat, or for the temporary accommodation of a commander-in-chief of a squadron who may desire to communicate rapidly with his ships at distant points. She is well fitted for the service, and is now in commission, demonstrating her ability to perform the work required of her. She could also be of service as a commerce destroyer, for which service she is equipped with one gun of long range. Her length is 240 feet, beam 32 feet, draught of water 14.25 feet. She has a displacement of 1485 tons, and attains a speed of 15 knots per hour.