should be heated to near the flash point of the fuel in order that this may at once be in a condition to burn freely as soon as atomized.

The ships in the Caspian Sea use steam, but are never far from land. Fuel may be injected under pressure and break up against an obstacle at the furnace mouth, or it may be vaporized by heat before reaching the furnace mouth.

In Mr. Howden's modification, fuel is injected under pressure mixed with air previously heated by the waste chimney gases, and this system has been fitted

Fig. 5. ARRANGEMENT OF FURNACE BRICKWORK, SS. MUREX

to the North German Lloyd steamers Tanglier and Packman; by Workman, Clark & Co., of Belfast.

In the ss. Murex already named, which arrived in the Thames in the spring of 1902 from a voyage of 11,800 miles, from Singapore viâ the Cape, the furnaces were never touched. Her coal consumption averaged 25 tons per day. With oil fuel the daily consumption is 16 tons only. The fuel supply arrangements, fig. 4, consist of steam pipes A A A A, oil pipes B B B B, and burners C C C C, hung on swivels D, so as to be adjustable in position, and to allow the doors to open upon the same axis or hinge centre. Coal can be reverted to, when the burner

orifices F F F F are closed by the pivoted slides. In fig. 5 is shown the brick work H H in the form of pillars and arches against which the flames first impinge. At K K K are further baffle bridges to keep the flame from too severely striking the back of the combustion chamber carrying the stay nuts, the tube ends, rivet seams and parts liable to injury from excessive local heat. The form of burner is the

Rusden-Eeles

type, fig. 6, with adjustable annular orifices both for steam and oil. They possess that apparent essential quality of adjustability while at work in order to secure

the most perfect possible conditions of combustion. The oil annulus is surrounded by a steam jacket, and steam enters the middle chamber and escapes into the furnace round the central stem P which is drawn back by revolving the wheel N, and allows an annular spreading steam jet to escape round the flaring end of the stem P. Oil finds its way to the little ring chamber immediately at the nozzle, and is directed down the sloping ends of the slide directly upon the steam jet which pulverizes it and spreads it in the furnace. The oil slide is drawn back by revolving the handle L.

The packing rings B and J are self-explanatory and prevent back flow of oil or of steam at the spindles.

Interchange of Coal and Oil.

To permit the ready interchange of coal and oil the ss. Trocas was fitted as in fig. 7, the coal grates remaining and being covered with 8 inches of broken brick. The brickwork B, C and D always remains in place.

To change over from oil to coal the burners are swung back to clear the furnace door, the broken brick is raked out and ordinary coal firing resumed. In twentyeight minutes after steaming full speed under oil the Trocas was again at full speed

under coal.

It is, however, found as the result of experience of long voyages that it is better not to let the firebars remain in when using oil, for, at the worst, the change over can be made in a few hours and better results obtained from oil with the more approved arrangement. The general arrangement of the ss. Trocas is that of fig. 4.

It is estimated by Sir Fortescue Flannery that the atomizing steam will amount

to 0-2 pound per i.h.p. per hour. The waste is made up by large evaporators, usually in three interchangeable sections which should be worked steadily.

Two burners in each furnace are found to give better results than one larger

burner, being more easily adjustable and maintaining continuity of flame. There is also greatly diminished chance of extinguishment of the flames by an accidental access of water from imperfectly dried oil.

The Flannery-Boyd System for Steam Ships.

The chief object of the system is to separate from the oil fuel the water which may have become mixed with it in any manner and also to enable oil fuel to be carried in ballast tanks or other compartments of a vessel where water is usually carried as ballast or for trimming purposes.

To get rid of the water two or more settling tanks are used, in which the oil is allowed to remain a sufficient length of time to permit of the water being deposited. In each tank a heating apparatus is introduced to assist the action, as it has been found by heating the oil within certain limits the water is more quickly deposited, owing to the expansion of oil being greater than that of water, and also because the oil is made less viscous by heat. Two or more tanks must be used, so that while the water is being deposited in one tank the dried oil in the other may be fed to the burners. The system is applicable, of course, to all or any system of burning oil.

It is illustrated in fig. 8 in diagrammatic form, showing the various pipe arrangements, etc., the oil feed pump 3 drawing from the ballast tank 1 through a pipe 4 and delivering by pipes 5 to the service tanks 22, whence the oil gravitates by way of pipes 7 to the oil burner supply pipes 9. Overflow pipes 13 carry back any surplus oil to the main tanks, and water separated in the service tanks is discharged by way of pipes 12.

The service pipes are kept free of pressure by vent pipes 14, carried up several feet.

The general arrangement of an oil ship is described under the head of carriage of oil, and one of the latest examples, the ss. Newyork, is illustrated in fig. 117, Chapter XXXI.

The Orde System.

In figs. 9, 9a, 10, 11 are shown various arrangements of oil fuel burning by Sir W. E. Armstrong, Whitworth, and Co., of Newcastle-on-Tyne, according to the system of Mr. C. E. L. Orde.

Fig. 9 shows the general arrangement for a water tube boiler. Steam, superheated in the casing by means of a pipe carried round the steam dome, is taken to a subsidiary steam header whence branch pipes issue to five separate burners. Oil is fed by similar pipes from a second header supplied from the bunker or oil