THE HONG KONG GOVERNMENT GAZETTE, MARCH 5, 1937.
safety lamps, the action of wire gauze diaphragms, and the places in which such protective devices should be fitted.
(2) A candidate for an Ordinary Certificate must also be prepared to be examined in the following subjects:-
(a) the methods of constructing marine steam engines and boilers, as used in the workshops, the processes to which the several parts are submitted, or which are incidental to their manufacture; and the methods employed in fitting the machinery on board ship;
(b) the various designs of paddle and screw steam engines (including turbines) now adopted; the functions of each important part; and the attention required by the different parts of the machinery on board ship;
(c) the methods of testing and altering the setting of the steam admission and exhaust valves; and the effect produced in the working of the engines by definite alteration of the valves' setting;
(d) the construction and working of evaporators, feed heaters and feed filters;
(e) marine boilers of various modern designs; the manner of staying them, and also of preventing their movement when the vessels in which they are fitted are rolling heavily, etc.; the determination, by calculation, of a suitable working pressure for a boiler of given dimensions;
(f) the use and management of boiler fittings and mount- ings, with special reference to the water gauges and safety valves; the precautions necessary to be taken when raising steam, and when opening stop valves to admit steam to steam pipes, etc.;
(g) the installations generally employed respectively for forcing draught, superheating steam, and burning oil fuel; the attention they require when working, and the care necessary for their maintenance in satisfactory condition.
(3) A candidate for a Motor Certificate is also required :—
(a) to be able to give a clear explanation of the principles on which oil, gas, or other internal combustion engines work, including the methods of ignition; to point out the differences between them, and to show, by means of sketches and other- wise, that he understands the details of the construction of those in general use;
(b) to be familiar with the various methods of supplying air and fuel to the cylinders of engines of different types; the construction of the apparatus for carburetting, atomising or gasifying the fuel; the means of cooling the cylinders, pistons, etc.; and the construction and working of air compressors;
(c) to have a satisfactory knowledge of the methods of constructing marine internal combustion engines, as used in the workshops; the processes to which the several parts are submitted, or which are incidental to their manufacture; and the methods employed in fitting the machinery on board ship;
(d) to know what attention is required to be paid to the various parts of the machinery; and to understand the use
157