JUNE 20.] . THE NEW ZEALAND GAZETTE. 1891

2. In accordance with these clauses a candidate for a first-class certificate is required to make a rough working-drawing of the parts specified, as on pages and . An engineer who has been some years in charge of marine engines and boilers ought by this time to have familiarly in his mind the general construction of at least one set of engines and boilers—say, that set he was last with. Fine drawing is not expected, and in the proportion of the parts a wide margin will be allowed. Absurd dimensions will be failure in practical knowledge.

3. The drawing must, however, be practically a working-drawing, giving a sufficient number of views to show the parts fully—sections, plans, or elevations, just as the candidate would require to be supplied to him if he had to make the parts to the design of another person.

4. A clear hand-sketch, showing the construction completely, and fully dimensioned, will be accepted if the candidate prefers this alternative.

5. A portion only of the parts specified may be accepted in place of the whole, if that portion is sufficient to show that the candidate has a good practical idea of the construction of the parts, and a fair notion of their general proportions or dimensions.

6. Candidates are hereby cautioned not to put on paper what they have not fully considered, and deliberately intend to be understood, as their statement of what they know about the construction of any part required.

7. The statements given in by a candidate may be in themselves apparently of little importance; but, as sample material from which the state of the candidate’s knowledge of engines and boilers is to be inferred, every detail which is glaringly inconsistent with a sound knowledge of the use of the part, or in which an essential consideration has evidently been overlooked, is an important element in the description which the candidate is giving of his own qualifications.

8. The candidate is advised not to begin more than he can clearly finish in the time allowed. An important object in this part of the examination is to ascertain whether the candidate can be trusted to mark all necessary dimensions upon a sketch or a drawing. The test of this is practically the making of the part from the sketch without having to supply additional dimensions, and without measuring the drawing. To prove this ability the candidate must fully dimension the parts shown in his sketch or drawing, notwithstanding that the parts may be correctly drawn to scale. A drawing is fully dimensioned when no part of it is left to the option of the party who is to work to the drawing.

9. To prevent misunderstanding, however, when the candidate has been led into showing more of the details than he has time fully to finish, he should name, in the statement on the other side, the particular parts which he has fully dimensioned.

10. All dimensions should have lines and darts, to indicate distinctly the points between which the dimensions are given.

11. Beware of writing cross-dimensions upon centre lines, or upon longitudinal-dimension lines. [This is not an order, but a recommendation.]

12. The candidate is not expected to design anything; he has merely to sketch or draw something with which he is expected to be already familiar. At the same time he should call attention to any defect in the design of the article or apparatus. Omission to do so will imply want of practical knowledge.

13. Pencil in nothing after half past 3. All the dimensions, the figures, and the darts must be inked in. Employ the remaining time in examining the drawing and in inking in any figures which may have been before overlooked, and in checking the dimensions.

14. Make sure that you will have sufficient room on the drawing-sheet to show all the necessary views. You can have another sheet of drawing-paper if necessary. All the paper used must be forwarded with the drawing.

(Specimen.)

SUBJECT FOR EXAMINATION IN ROUGH WORKING-DRAWING.

Form Exn. 17a.

(Read the foregoing General Instructions.)

A COMMON SLIDE-VALVE, with its spindle. Show also an outline section of the ports at the cylinder-face. Show the provision for connecting the slide-valve to the spindle.

The candidate is requested to fill up the following, and to attach this paper to his drawing.

Statement by the Candidate.

The accompanying drawing, made by me this day without referring to any document, and without the assistance of any person, is intended by me to be sufficient for the new construction of the parts above described, to fit the places of similar parts which are to be removed. The construction is similar to what I have been with in the steamer , but the dimensions may be different.*

The diameter of the cylinder is .

The stroke of the piston is .

The stroke of the valve is .

The cover at top end on steam side is .

The cover at bottom end on steam side is .

The lead at top is intended to be .

The lead at bottom is intended to be .

The inside cover is + or —

The thickness of the face of valve is .

The thickness of the body of valve is .

The greatest opening for steam will be .

That gives an area equal to one .

The opening for exhaust when the crank is on the top centre is .

That gives an area equal to th of piston.

† The length of the connecting-rod is .

† The valve will cut off steam on the downstroke at .

† The valve will cut off steam on the upstroke at .

The parts fully dimensioned in ink are .

Dated at , this day of , 19 .

Applicant.

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APPENDIX D.

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READING THE WATER-GAUGES.

Notwithstanding that the reading of the water-gauge is made a special feature in the examination of engineers, many boiler casualties result from the engineer of the watch either not understanding the construction of the water-gauge fittings or not satisfying himself by actual trial that the cocks, pipes, &c., are clear.

• Run the pen through the words that do not apply.

† The candidate may omit this part if he chooses.