MAR. 5.] THE NEW ZEALAND GAZETTE. 503

9. Describe the construction and working of an independent boiler feed-pump. What are the advantages of an independent pump as compared with a feed-pump driven by the main engines?

10. State the chief advantages incident to the use of the condenser. Describe, with sketches, the construction of a surface condenser of common design, indicating the courses of the cooling-water and the steam. Show the method of preventing leakage of cooling-water at the ends of the tubes.

11. Explain what is meant by the term "compounding" as applied to reciprocating steam-engines. What benefits are derived from compounding? Describe the method of compounding usually adopted by marine-engine builders.

12. What precautions should be taken when opening stop valves to admit steam to steam-pipes? Explain why these precautionary measures are necessary.

FIRST CLASS.
First Paper.

The questions are not to be copied. The answers should be written on form Exn. 30. Extra paper will be supplied if required. Do not deface or make any marks whatever on this paper.

1. Describe the construction of a modern high-pressure boiler of the water-tube type. What are the advantages and disadvantages of a marine water-tube boiler as compared with a cylindrical multitubular boiler?

2. What is the average chemical composition $(a)$ of mild steel; $(b)$ of cast iron; $(c)$ of cast steel; $(d)$ of brass; $(e)$ of white metal? Describe the physical characteristics of each of these materials, and state for what parts of the engines and boilers it is usually adopted and why.

3. What is meant by the "mechanical equivalent of heat"? Explain how the heat energy of the fuel is converted into useful work $(a)$ in reciprocating steam-engines; $(b)$ in steam-turbines.

4. Give a brief description of a Parson's steam-turbine. Indicate the course of the steam through the turbine, and explain its action on the blades. Why is it important that a high vacuum be maintained in the condenser of a turbine-driven vessel?

5. What advantages are to be derived from feed heating? Describe the construction and working of a feed-water heater usually found on board ship.

6. Describe an electric steering-gear. Explain clearly the action of the hand- and automatic-controlling arrangements.

Second Paper.

7. Write a report addressed to your superintendent engineer describing any breakdowns or defects in marine engines or boilers of which you have knowledge. State the causes of the defects and the methods of repair adopted, and explain how they might have been prevented.

8. Explain how the stability of a ship is affected by ballast-tanks in partly filled condition. State the means usually adopted in oil-burning vessels to minimize the effect of "slack" tanks.

9. State the causes and effects of the formation of scale and the precipitation of salt in marine boilers, and mention the precautionary measures usually adopted.

10. Describe, with sketches, the construction of the engine-seating of a modern steamship fitted with reciprocating engines. Show clearly how the engines are secured to the ship's structure, and how movement of the engines relative thereto is prevented.

11. Explain clearly the action of the screw propeller. State what is meant by the apparent slip of a propeller, and how it is determined. What is negative slip, and what does it indicate?

12. Describe any system of pulverized-fuel firing with which you are familiar. Discuss the relative merits of pulverized-fuel firing and hand-firing methods as applied to marine boilers.