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and the other part the skeins which have none of the test skeiu colour in them. The examiner should explain that there is no exact match for the test skein, as the skeins which contain this colour are all either lighter or darker, and that the only question is the division of those skeins which contain the test colour more or less from those which do not. No difficulty should be experienced in explaining to the candidate what he is required to do, but if the examiner thinks he has not grasped what is required he may himself divide the heap into two parts as a demonstration, mixing the skeins up again thoroughly before allowing the candidate to do the test. 4. When the candidate has dealt with the first test skein each of the four remaining tests should lie gone through in a similar manner and in the order named. 5. As the examination proceeds the examiner should place on one side the skeins which the candidate has wrongly selected as either resembling or not resembling the test skeins, and when the examination is finished a small piece (say, 1 in.) should be cut off every one of the actual skeins incorrectly selected by the candidate, and stitched to Form Exn. 17c under the proper heading in the spaces provided for each test. 6. The greatest care must be taken that the pieces forwarded are cut off the actual skeins selected by the candidate, in order that there may be a reliable record of the actual selections made by the candidate if any question should subsequently arise. 7. During this test the examiner should avoid naming the colours of any cf the wools, and should explain to the candidate that he does not require them to be named by him. 8. The wool test should only be held in daylight. If a good natural light is not obtainable the test must be postponed. If dark or foggy weather renders it necessary to postpone the examination until after the examination in navigation or seamanship has been begun, the examiner should not fail to inform the candidate that the latter examination will be cancelled in the event of failure to pass the sight tests. //. The Lantern Test. 9. A special lantern and a mirror have been provided for this test. The lantern should be placed directly in front of the mirror, so that the front part of the lantern is exactly 10 ft. from the mirror. Care should be taken that the lantern is properly placed —that is to say, the lights reflected in the mirror must show clearly when viewed through the rectangular aperture on the left of the lantern. The examiner should always satisfy himself that these conditions are fulfilled before commencing the examination. 10. It is essential that a candidate should be kept in a room which is either completely or partially darkened for at least a quarter of an hour before he is required to undergo this test. 11. Before the examination commences the examiner must satisfy himself that the room in which it is conducted is so darkened as to exclude all daylight. 12. The lantern supplied for the examination is so constructed as to allow one large or two small, lights to be visible, and is fitted with twelve glasses of three colours —red, white, and green. At the commencement of the examination the examiner should show to the candidate a series of lights through the large aperture, and should require him to name the colours as they appear to him. Care should be taken in showing the white light to emphasize the fact that the light is not a pure white. If a candidate makes a mistake of calling this light " red," a proper red light should be shown immediately after, and the candidate's attention directed to the difference between the two. After a series of lights through the iarge aperture has been shown, the examiner should make a complete circuit with the two small apertures, requiring the candidate to name the colours of each set of two lights from left to right.- To prevent any possibility of the order in which the lights are arranged from being learnt, the examiner should at least twice in each circuit go back a varying number of colours. He should keep a record of the number of the glass with which he began the series, and should take care to vary it from time to time. A record of any mistakes made with either the large aperture or the two smaller apertures should be kept on Form Exn. 17c in accordance with the instructions thereon. 13. As the lantern itself forms a test for colour-ignorance, the old colour-ignorance test becomes unnecessary, and should be discontinued. ///. Success or Failure. 14. If a candidate with either the large aperture or the two smaller apertures of the lantern mistakes red for green or green for red, he should be considered to have " failed " in colour vision. 15. If a candidate makes no mistakes in the wool test, and if the only mistakes made by him with the lantern is to call the white light " red," and if after his attention has been specially directed to the difference between the two he makes no further mistake of this nature, he should be considered to have passed in colour vision. 16. If a candidate makes any other mistake with the lantern— i.e., if he calls white " red " repeatedly or red " white " at all, or confuses green and white, or if he makes any mistake whatever in the wool test —his case should be reported to the Principal Examiner of Masters and Mates, and he should be told that the decision as to whether any further examination is necessary or not will be communicated to him in due course. Pending the receipt of the Principal Examiner's instructions, such a candidate should only be allowed to proceed with the remainder of the examination for a certificate of competency on the express understanding that the latter examination, will be cancelled in the event of failure in the sight tests.

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