It has been well pointed out by Mr A. Betts Brown, of Edinburgh, the patentee and manufacturer of this class of machinery, in a paper read by him before a recent meeting of the Institution of Naval Architects that—“With all the noise of steam engines at work on deck, running at piston speeds of as much as 1000 feet per minute, the cargo is lifted from the hold at a rate of only from one to two feet per second, which cannot be considered as keeping pace with the general progress made in other departments of steamship economy. In short, vast sums are spent on fuel to gain half a knot extra speed on a passage, while hours may be wasted in port in consequence of the primitive nature of the present system of deck machinery for discharging cargo.” Previous to 1880, Mr Brown had supplied and fitted hydraulic machinery on board the paddle-steamer _Cosmos_, built by Messrs A. & J. Inglis, of Glasgow, intended for South American river service, but it was only in that year that he had an opportunity of fitting a large ocean-trading steamship with the system. This was the _Quetta_, built by Messrs Denny, Dumbarton, to whom, with the managers of the British India Association Steam Navigation Company, who own the vessel, Mr Brown ascribes credit for the opportunity afforded him of fitting his firm’s system on a complete scale. The _Quetta_ is 380-ft. in length, 40-ft. breadth, depth of hold 29-ft., and 3,302 tons gross, and is fitted with a complete system of hydraulic machinery performing the following functions:—Steering, heaving the anchor, warping by capstans fore and aft, taking in and discharging cargo, lowering the derricks to clear cargo over side, hoisting ashes, reversing main engines, and shutting tunnel water-tight door in engine-room. For detailed descriptions of these various appliances, the reader is referred to the before-mentioned paper. The most for which space is here available is a very general outline of the principle on which they are supplied with motive power. The prime mover consists of a pair of compound surface-condensing pumping engines of 100 indicated horse-power, situated in the engine-room of the vessel. These engines pump water (or in winter non-freezing fluid) from a tank into a steam accumulator. The pumping engines are started and stopped by the falling or rising of the steam piston in the accumulator; and since the piston falls when the hydraulic power is being utilised, and rises to its former level when the power is not in use, it follows that the apparatus is perfectly automatic. Once started, it does not require the supervision of an engineer, and it maintains a steady pressure of 800-lbs. per square inch in the hydraulic mains or pressure pipes. These are carried up from the engine-room, and extend fore and aft the ship. Alongside the pressure main a similar return main is laid, which discharges into the tank. From the pressure mains branches are connected to the various hydraulic machines.