_Pietro Micca_ (Italian). This vessel, having a displacement of about 530 tons, is built very low in the water, with a curved deck or cover, and is not armored except as regards a deck under the curved cover and over the engines, intended to resist the penetration of plunging projectiles, and which is of laminated steel 2¼ inches thick. Her estimated speed is 18 knots, and she is provided with tubes for discharging Whitehead torpedoes ahead, abeam, and astern. _Rau_ (Swedish). _Ziethen_ (German). _Vesuvius_ (English). _Uzreef_ (Russian). Whitehead torpedo gun-boats of from 400 to 700 tons displacement and an estimated speed of from 13 to 16 knots. The peculiarity of the Vesuvius is in having an elbowed smoke-stack carried along the deck. The Rau carries a light rifled gun. All carry machine-guns. _The Alarm_ (American). The Alarm is an iron ram gun-boat, built on the transverse bracket system, with a double bottom and water-tight bulkheads every 25 feet. Her dimensions are: length, 173 feet; beam, 28 feet; draft, 11 feet—which may be increased by sinking the vessel to the level of the upper-deck beams, arrangements having been made for the admission and ejection of water in the compartments formed by the double hull. The torpedo system of this vessel consists of three hollow steel tubes, one projected from the end of the ram a distance of 30 feet, and one from each broadside, 17 feet. These tubes slide in and out on frames, and are worked by small auxiliary engines and winches; the torpedo is fitted to the end of the spar and is fired by electricity. The port from which the spar is projected, being below the water-line, is provided with a water-box and double doors and heavy rubber washers, which grip the spar water-tight as it is run out. In addition to the torpedo system, this vessel is arranged to carry a 10-inch rifle forward. Her ram is strengthened, and her bow is protected for some distance by a plating of 4½ inches. On her rail she carries machine-guns to resist the attack of torpedo-boats. Her propeller is of a novel pattern, serving as steering-gear and propelling power. This vessel was originally fitted with a propelling apparatus known as the Fowler steering-wheel, a novel propeller which both gave the vessel headway and steered her. The blades of the propeller were worked by means of a simple steam-valve arrangement manipulated by the helmsman. The steering qualities with this apparatus were little short of marvellous, as she could be driven and steered with as great facility astern as ahead, and could even be worked sideways. Her speed, however, was deficient, never reaching ten knots. At present the vessel has been fitted with the Mallory steering propeller, a form of screw with a jointed shaft so that it may be revolved about a vertical axis. This screw promises to give a speed more nearly warranted by the fine lines of the vessel. _The Intrepid_ (American).