Mar. 5.] THE NEW ZEALAND GAZETTE. 509

weight is moved, all other tanks being full. The double-bottom fuel-tanks are subdivided longitudinally by the centre girder. The above tank is subsequently filled, and in consequence the centre of gravity of the vessel is lowered half an inch. Find the metacentric height after the tank has been filled, neglecting the slight increase in draught due to the additional oil.
(50 marks.)

14. A vessel having a block coefficient of 0·75 is 350 ft. long, 44 ft. beam, and 22 ft. draught. The speed of the propeller is 80 revolutions per minute, the pitch 18 ft., the diameter 16½ ft., and the diameter of the boss 3½ ft. The total resistance experienced by the vessel is expressed by the formula—
    R = f AVⁿ, where
    f = the coefficient 0·009
    A = the area of the wetted surface of the hull in square feet.
    V = the speed of the ship in knots.
    n = the index 2.
    Assuming the hull efficiency to be unity and the propulsive efficiency 0·5, find—(a) the speed of the vessel in knots, and (b) the horse-power of the engines.
    (50 marks.)

Note.—The area of the wetted surface of the hull may be determined by the formula—
A = 2 LD + V/D, where
D = the draught in feet.
L = the length in feet.
V = the volume of displacement in cubic feet.

15. Describe, with sketches, the construction of the cellular double-bottom of a twin-screw motor-ship in way of the engine-room, giving particulars of the scantlings. Show in detail the arrangement of the engine-seatings, and explain the methods employed in their construction.
    (45 marks.)

16. Give a brief description of a system of electric propulsion, and explain how reversal of the main motors is affected. Describe the arrangement and action of the control-gear, indicating clearly the method of controlling the speed of the propelling-motors. State the advantages and disadvantages of the electric drive as compared with other methods of propulsion.
    (55 marks.)

Third Day: 9.30 a.m. to 3.30 p.m.

Draw, to scale, either of the following subjects—
(a) A “Yarrow” marine-type water-tube boiler suitable for a working-pressure of 350 lb. per square inch and an evaporative duty of approximately 20,000 lb. per hour. Give full particulars of the drum riveting and of the spacing of the tubes, and show how the tubes are fitted to the drums. Particulars of the drum manholes and manhole-covers are also required; and the blocks for the various mountings should be shown in place, and the method of securing the boiler to its seating indicated. (Note.—The boiler-casing need not be shown in detail. A diagrammatic arrangement of the casing will suffice.)

(b) A fuel-pump for a single-cylinder four-stroke cycle single-acting Diesel engine of the air-injection type, showing in detail the mechanism of the fuel-regulating arrangement. The engine develops 250 indicated horse-power at 130 revolutions per minute.

Sufficient views and dimensions should be given to permit of the various parts depicted being made from the drawing, and the materials of which the several parts are to be made should be indicated thereon. A pencil drawing only is required, but the dimensions and corresponding arrow-heads should be in ink. Credit will be given for neat workmanship.
(120 marks.)

Fourth Day: 9.30 a.m. to 1.30 p.m.

Write an essay dealing with one of the following subjects:—
(a) The Relative Merits of Diesel-electric and Turbo-electric Propelling Machinery for Large Passenger-vessels.
(b) The Education of the Marine Engineer.

A rough draught may, if desired, be made, but it should be handed in with the finished copy, which should occupy at least four pages. Marks will be awarded for composition, spelling, punctuation, and writing as well as for the technical knowledge displayed.
(100 marks.)