ORDINARY EXAMINATION.

EXAMINATION PAPER, No. I.

For Second Mate.

(1.) Multiply 489 by 324, by common logarithms. (2.) Divide 956 by 49, by common logarithms.

(3.) In latitude 53°, the departure made was 118 miles; required the difference of longitude by Parallel Sailing.

(4.) In the following day's work, correct the courses for variation and leeway; find the course and distance made good, and the latitude and longitude in, by inspection :

(5.) October 22, 1866—when the sun's declination was 11° 12′ 16′′ S., the observed meridian altitude of his lower limb was 23° 16′ 40′′ south of the observer; index error - 1′ 12′′, and height of the eye, 18 feet; required the latitude.

(6.) Required the course and distance from lat. 51° 12′ N., long. 11° 6′ W., to lat. 48° 23′ N., long. 15° 35′ W., by Mercator's Sailing.

Additional for Only Mate.

(7.) On December 8, 1866, at 4 h. 30 m. 40 s. P.M. apparent time at ship, in lat. 42° N., long. 8° 10' W., the sun's setting amplitude was observed to be W. N.; required the variation of the compass.

(8.) On November 13, 1866 P.M. at ship, in lat. 47° 50' S.; the observed altitude of the sun's lower limb was 20° 46′ 20′′; index error, 2′ 15′′ to add; height of the eye, 22 feet; time by chronometer, November 13 d. 7 h. 12 m. 20 s., which was fast for Greenwich mean time 4 m. 33 s. on the 1st October at noon, and losing 4.5 s. daily; required the longitude.

Additional for Chief Mate.

(9.) On February 9, 1866-in lat. 44° 13′ S., long. 58° 34′ 45′′ E., at 5 h. 14 m. 14 s. P.M., mean time at ship; the observed altitude of the sun's lower limb was 20° 45' 10"; index error, 2' 30" to subtract; height of the eye, 18 feet; sun's bearing by azimuth compass W. 12° N.; required the variation of the

compass.

(10.) On October 23, 1866—P.M. at ship, latitude by account 41° 45', longitude 94° 24′ E.; observed altitude of the sun's lower limb, south of the observer, was 36° 15′ 20′′; index error +1′ 15′′; height of the eye, 20 feet; time by watch, 23 d. 2 h. 12 m. 15 s., which had been found to be 1 h. 40 m. 36 s. fast on apparent time at the ship; the difference of longitude made to

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the east, since the error of the watch on apparent time at the ship was determined, was 45'4; required the latitude by reduction to the meridian.

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Additional for Master Ordinary.

(11.) On October 24, 1866, the observed meridian altitude of a Canis Majoris (Sirius) was 38° 15′ 35′′, south of the observer, index error + 1° 25′′; height of the eye, 22 feet; required the latitude.

(12.) Correct the following courses for local attraction (by the accompanying Table of Deviations): NW. W.; E. by N. & N.; NNW. W.; NE. E.; W. by S. S.; and ESE. S.

Answers.

(1.) Log. 5.1998539 = nat. number, 158436. (The product.) (2.) Log. 1.2902618 = nat. number, 19.5102. (The quotient.) (3.) Dif. long. 3° 16'.

W. 25 miles; S. 27 miles; S. 2

(4.) True courses-S. E. 10 miles; S. 1 13 W. 26 miles; S. 1 E. 36 miles; S. E. E. 25 miles; N. E. 16 miles; dif. lat. 127.5 S., dept. 7.7 E;

course, S. 3 E.; dist. 128, by inspection; course, S. 3° 28′ E. and distance 127.73, by calculation; lat. 49° 17 N.; long. 9° 17' W.

(5.) Lat. in 55° 22′ 20′′ N.

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(6.) Mer. dif. lat. 261.9, dif. long. 269'; course, S. 45° 5' W.; dist. 190.12 miles.

(7.) App. Gr. time, 5 h. 3 m. 55 s.; sun's dec. 22° 45′ 44′′ S. ; true amplitude, W. 31° 22' 30" S.; variation, 33° 11' 15" W.

(8.) Mean Gr. time, Nov. 13, 7 h. 11 m. 2 s.; sun's dec. 18° 4′ 33′′ S.; mean time at ship, 4 h. 58 m. 15 s.; long. 33° 11′ 45′′ W.

(9.) Gr. mean time, Feb. 9, 1 h. 19 m. 55 s. P. M.; sun's dec. 14° 37′ 28′′ S.; true azimuth, S. 89° 39′ 29′′ W.; variation, 12° 20′ 31" W.

(10.) App. time past noon at observation, 34 m. 40 s.; mean Gr. time of obs. Oct. 22, 19h. 4 m. 26 s.; sun's dec. 11° 21′ 38′′ S.; arc I = 101° 29′ 18′′; arc 2 = 53° 4′ 33′′; lat. in 41° 35′ 15" N.

(11.) Trué dec. 16° 32′ 8′′.61 S. ; true alt. 38° 11′ 16′′ S.; lat. 35° 16′ 35′′ N.

(12.) Corrected courses, N. 59° 12′ W.; N. 84° 19′ E.; N. 33° 42′ W.; N. 58° 41′ E.; S. 63° 11′ W.; S. 53° 38′ E.

EXAMINATION PAPER, No. II.

For Second Mate.

(1.) Multiply 1866 by 429, by common logarithms. (2.) Divide 34650 by 185, by common logarithms. (3.) In latitude 56° the departure made was 208 miles; required the difference of longitude by Parallel Sailing.

(4.) In the following day's work, correct the courses for variation and leeway; find the course and distance made good, and the latitude and longitude in, by inspection :

(5.) On October 22, 1866-longitude 71° 30' W.; observed meridian altitude of sun's lower limb was 60° 18′ 40′′; observer north of the sun; index error, 1' 12" to subtract; height of the eye, 22 feet; required the latitude.

(6.) Find the course and distance from lat. 48° 12' N., long. 12° 30' W., to lat. 23° 34' N., long. 53° 27' W., by Mercator's Sailing.

Additional for Only Mate.

(7.) On October 22, 1866, at 5 h. 23 m. 25 S. A.M. apparent time at ship; lat. 39° 16' S., long. 22° 45′ W.; the sun's rising amplitude was observed to be E. 12° 34' N.; required the variation.

(8.) On October 3, 1866-A.M. at ship, lat. 36° 17' S.; observed altitude of sun's lower limb, 26° 54'; index error, 55" to add; height of eye, 19 feet; time by chronometer, October 2, 15 h. 34 m. 20 s., which had been found 1 m. 21 s. slow on mean