The cargo “tramps,” built about 1902, were on an average about 350 feet long, 2800 tons gross and 4000 tons dead weight. In build they were of the poop, bridge, and forecastle deck type with main deck below the upper deck, and fitted with double bottoms. The appliances for working cargo are extraordinarily complete and effective. To each hatch there are usually two winches and two derricks, having 5 tons lift each, with, as a rule, a heavy derrick capable of lifting from 20 to 30 tons; the last is portable, so that it can be used at either of the two main hatches. Cathead davits have been dispensed with as, with stockless anchors, they are not required owing to the anchors stowing up the hawse pipes. Officers, &c., are berthed in deckhouses built on the bridge deck, leaving the bridge ’tween deck clear for cargo. Electric light and steam-heating are fitted to all rooms, advantages not enjoyed by older boats. About the year 1904 the shelter-deck type reached its present stage of perfection, the advantage of this type being increased cargo capacity on a small net tonnage. The accommodation of officers and engineers is fitted in midship deckhouses and side houses. Much more attention is now paid to the ventilation of the holds and ’tween decks, more especially in coal-carriers, where efficient ventilation is of the highest importance. The adoption, within very recent years, of wide-spaced pillars in holds and ’tween decks has greatly improved the facilities for stowage of large cargo. The four desiderata of a modern cargo-boat are that she should have a low registered tonnage in comparison with her capacity, ample water-ballast tanks, large hatchways, and holds as free from obstruction as possible. Three or four methods are practised by builders for attaining these objects, and every builder has made modifications of them as time has shown the necessity of the changes to meet varying trade conditions. The principal types of cargo vessels are the turret, trunk, cantilever, and side tank.