3-047-107 - The Print Collector/Heritage Images

Plan of the Mackie Channel passage steamer, 1872. 'The vessel is constructed in the following manner: The bottom of the hull is nearly flat, there being just a slight rise along the median line. It is double plated, with an interval of 18 in. between the skins. Four main vertical girders at, bu, cv, dw, extend longitudinally through the vessel from end to end, so far as the form of the bows and stern will permit. These girders are braced together transversely, by a main deck and by an upper or promenade deck, the whole being attached to the outer skin, m s t u v w x r, of the vessel. The central interspace, A A, formed by the innermost longitudinal girders, constitutes the main compartment, or central hull, of the vessel; and in this are placed the boilers, engines, stores, berths for crew, and cargo. The lateral interspaces, B B, between the inner and outer longitudinal girders, form on each side a tubular channel or waterway, open at both ends; and within these waterways are the propellers, which may be two or three pairs of paddles in each waterway, to work synchronously or separately, at the will of the engineer, who controls all the engines from a central position under the steering-house'. From "Illustrated London News", 1872.