Aug. 2.] THE NEW ZEALAND GAZETTE. 3103

ship’s deck, varies as the ship changes her geographical position.

88. What, then, would be the probable nature of the heeling error—that is, whether to high or low side of the ship; and whether the error would be equal to the sum or difference, &c., of the forces given (1) in high north latitude, (2) on magnetic equator, (3) in high south latitude?—assuming the polarity of the subpermanent magnetism of the ship under and affecting the compass to be as given below; the vertical induction in soft iron, of course, obeying the ordinary laws in the above geographical positions (1), (2), (3):

(a.) In cases where the effect of red vertical subpermanent magnetism is equal to that of the vertical induction in the soft iron of the ship:

(b.) Where the effect of red vertical subpermanent magnetism is greater than that of the vertical induction in the soft iron:

(c.) Where the effect of red vertical subpermanent magnetism is less than that of the vertical induction in the soft iron:

(d.) Where the effect of blue vertical subpermanent magnetism is equal to that of the vertical induction in the soft iron:

(e.) Where the effect of blue vertical subpermanent magnetism is greater than that of the vertical induction in the soft iron:

(f.) Where the effect of blue vertical subpermanent magnetism is less than that of the vertical induction in the soft iron.

89. Can the heeling error be compensated? If so, state the means to be employed, and how the compensation may be effected.

90. Can the compensation of the heeling error be depended on in every latitude? If not, state the reason.

91. Do the soft-iron correctors used for compensating the coefficient + D have any effect on the compass-needle when the ship heels over, and, if so, do they draw the needle towards the low or the high side of the ship, and do they counteract, or otherwise, the effect produced by the vertical induction in the soft iron, (a) in the Northern Hemisphere, (b) in the Southern Hemisphere; and what is the reason of this?

92. Given the heel, the direction of the ship’s head by compass, and the heeling error observed: to find the approximate heeling error, with a greater or less given heel, and with the ship’s head on some other named point of the compass, the ship’s magnetic latitude being in both cases the same.

93. Describe any instrument to show the ship’s heel (generally called a clinometer), and state how and where it should be fixed.

94. Should the clinometer be observed when the ship is swung to determine the deviation when the ship is upright? If so, state the reason why.

95. Would you expect the table of deviations supplied by the compass-adjuster from observations made in swinging the ship to remain good during the voyage, or would you expect the deviations to change? If so, state under what circumstances.

96. Is it desirable that a record of your observations for deviations should be kept as a guide for any subsequent voyage in case the ship should be in the same locality, or for further corrections of the compass? If so, describe some suitable form for keeping such record.

97. Would you under any circumstances consider it a safe and proper procedure to place implicit confidence in your compasses, however skilfully they may have been adjusted? If not, what precautions is it your duty to take at all times?

F

APPENDIX L.
DEVIATION OF THE COMPASS.
FOR MASTERS’ CERTIFICATES FOR HOME-TRADE SHIPS.

The applicant must answer in writing, on paper given him by the Examiner, all the following questions, numbering his answers to correspond with the numbers of the questions:—

1. When taking a meridian altitude, how do you know when the sun is on the meridian; or, in other words, when it is noon?

2. How does the sun bear (true and magnetic) when on the meridian of an observer in these latitudes (home-trade limits)?

3. What do you mean by deviation of the compass, and how is it caused?

4. Having determined the deviation, how do you know when it is easterly, and when westerly?

5. On at mean New Zealand time at ship, in latitude S., longitude E., the sun bore by compass ; required the sun’s true bearing and error of the compass by the A, B, C Azimuth Tables:* and supposing the variation to be , required the deviation of the compass for the position of the ship’s head at the time of observation.

6. How could you find the deviation of your compass when in port, or when sailing along a coast?

7. Name some suitable objects by which you could readily obtain the deviation of your compass when sailing along the coasts of the channel you have been accustomed to see?

8. The bearing of two objects when in line with each other was found on the chart to be magnetic, but when brought in a line on board they bore by your compass; required the deviation of your compass for the direction of the ship’s head at the time.

9. What means are there for checking the deviation of your compass by night?

10. Do you expect the deviation to change? If so, state under what circumstances.

11. What is meant by the variation of the compass, and what is the cause of it?

APPENDIX M.
COMPASS-ADJUSTMENT.

It is of the utmost importance that masters of ships should thoroughly understand the tentative method of compass-adjustment as generally practised in merchant ships, and Examiners are therefore directed to fully satisfy themselves that all candidates for masters’ certificates have this particular knowledge. It should be tested in connection with the Forms Exn. 7 and 7a, with the aid of Captain Beall’s deviascope, and candidates will be required to prove (1) their knowledge of the laws of deviation and the tentative methods of compass-adjustment; (2) that they understand the practical application of the answers given by them to any of the other questions on Forms Exn. 7 and 7a that the Examiner may ask.

A concise statement of the present method of tentative compass-adjustment is appended for the use of Examiners. It is, however, distinctly to be understood that the Marine Department is not in any way advocating the correction of that part of coefficient B which arises from vertical induction in soft iron by a permanent magnet instead of by a soft-iron bar. The Department has no authority to interfere with the methods in use amongst compass-adjusters for the adjustment of compasses in iron ships, but the Examiners must satisfy themselves that masters are acquainted with the ordinary method as at present practised.

• The candidate may use any other time-azimuth tables should he prefer to do so.