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these Longitudes, as they are given to the Candidate after he has found the first two. These second two Longitudes are then laid off on the Chart in their respective Longitudes and joined by a straight line. Where this line cuts the line Č D is the position of the Ship. Then proceed to find the results as directed in Rules Nos. 9, 10 and 11. The results are as follow:—

Line of Position.. N 42° 11' E. and S 42° 11′ W.
Bearing of Sun . . S 47° 49′ E.

Lat. of Ship

....

Long. of Ship...

48° 26' N.

6o 14' W.

For answers to the following Sumner's, see end of book.

I. If at sea on April 21st, 1885, A.M., and uncertain of my position, when the Chronometer showed 21a 3h 15m 10o Greenwich Mean Time, the observed Altitude of the Sun's L.L. was 19° o' 30, and again A.M. the same day, when the Chronometer showed 21d6h 28m 385 Greenwich Mean Time, the observed Altitude of the Sun's L.L. was 47° 35′ 45′′, the ship having made 26 miles on a true West course in the interval, height of eye 16 ft. Required the line of position when the first Altitude was taken; also the bearing of the Sun, and the position of the ship by Sumner's method when the second Altitude was observed, the ship being supposed to be between the parallels of 47° 50' N., and 48° 30' N.

2. If at sea on March 9th, 1885, A.M., and uncertain of my position, when the Chronometer showed 8a 17h 35m 50* Greenwich Mean Time, the observed Altitude of the Sun's L. L. was 26° 19′ 40′′, and again P.M. the same day, when the Chronometer showed 8a 21h 52m53s Greenwich Mean Time, the observed Altitude of the Sun's L. L. was 34° 23' 38", the ship having made 24 miles on a true N.E. course in the interval, height of eye 21 feet. Required

the line of position when the first Altitude was taken; also the bearing of the Sun, and the position of the Ship by Sumner's Method when the second Altitude was observed, the ship being supposed to be between the parallels of 47° 10' N., and 47° 40′ N.

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3. If at sea on May 15th, 1885, A.M., and uncertain of my position, when the Chronometer showed 14d9" 29" 28" Greenwich Mean Time, the observed Altitude of the Sun's L. L. was 48° 34′ 50′′, and again P.M. the same day, when the Chronometer showed 14° 14h 2713 Greenwich Mean Time, the observed Altitude of the Sun's L. L. was 48° 33′ 23′′, the ship having made 17 miles on a true S.E. course in the interval, Height of Eye 22 feet. Required the line of position when the first Altitude was taken; also the bearing of the Sun, and the position of the Ship by Sumner's Method when the second Altitude was observed, the Ship being supposed to be between the parallels of 46° 20' N., and 46° 40' N.

4. If at sea on June 29th, 1885, A.M, and uncertain of my position, when the Chronometer showed 28d 9h 0m 40' Greenwich Mean Time, the observed Altitude of the Sun's L. L. was 46° 38′ 30′′, and again P.M. the same day, when the Chronometer showed 29d 14h 0m 40s Greenwich Mean Time, the observed Altitude of the Sun's L. L. was 56° 50' 33" the ship having made 32 miles on a true S. by E. E. course in the interval, height of eye 20 feet. Required the line of position when the first Altitude was taken; also the bearing of the Sun, and the position of the ship by Sumner's Method when the second Altitude was observed, the ship being supposed to be between the parallels of 46° 0′ N. and 46° 30′ N.

5. If at sea on July 27th, 1885, A.M., and uncertain of my position, when the Chronometer showed 26d 14h 300$ Greenwich Mean Time, the observed Altitude of the Sun's L. L. was 38° 5′ 39′′, and again A.M. the same day, when

the Chronometer showed 26d 16h 33m4s Greenwich Mean Time, the observed Altitude of the Sun's L. L. was 55° 45' 2", the ship having made 34 miles on a true W.N.W. course in the interval, height of eye 20 feet. Required the line of position when the first Altitude was taken; also the bearing of the Sun, and the position of the ship by Sumner's Method when the second Altitude was observed, the Ship being supposed to be between the parallels of 46° 50' N. and 47° 20' N.

6. If at sea on September 1st, 1885, A.M., and uncertain of my position, when the Chronometer showed Aug., 31 21 58mos Greenwich Mean Time, the observed Altitude of the Sun's L. L. was 42° 10' 20" and again P.M. the same day, when the Chronometer showed Sept. Id 2 540 Greenwich Mean Time, the observed Altitude of the Sun's L. L. was 37° 5' 0", the ship having made 20 miles on a true North course in the interval, Height of Eye 19 feet. Required the line of position when the first Altitude was taken; also the bearing of the Sun, and the position of the ship by Sumner's Method when the second Altitude was observed, the Ship being supposed to be between the parallels of 47° o' N. and 47° 40′ N.

7. If at sea on September 23rd, 1885, A.M., and uncertain of my position, when the Chronometer showed 22d 9h 16m8 Greenwich Mean Time, the observed Altitude of the Sun's L. L. was 31° 28′ 19′′, and again P.M. the same day, when the Chronometer showed 23d 15h 1946 Greenwich Mean Time, the observed Altitude of the Sun's L. L. was 24° 2′ 58′′, the ship having made 27 miles on a true N.E. by N. course in the interval, Height of Eye 20 feet. Required the line of position when the first Altitude was taken; also the bearing of the Sun, and the position of the ship by Sumner's Method when the second Altitude was observed, the Ship being supposed to be between the parallels of 47° 15′ N. and 47° 55' N.

8. If at sea on December 10th, 1885, A.M., and uncertain of my position, when the Chronometer showed 9°14h 227 Greenwich Mean Time, the observed Altitude of the Sun's L. L. was 11° 54′ 25′′, and again P.M. the same day, when the Chronometer showed 9d 18h 37m135 Greenwich Mean Time, the observed Altitude of the Sun's L. L. was 15° 38′ 26", the ship having made 34 miles on a true W.N.W. course in the interval, Height of Eye 19 feet. Required the line of position when the first Altitude was taken; also the bearing of the Sun, and the position of the ship by Sumner's Method when the second Altitude was observed, the ship being supposed to be between the parallels of 46° 25' N. and 46° 45' N.

9. If at sea on November 17th, 1885, A.M., and uncertain of my position, when the Chronometer showed 17d5h 44m 12s Greenwich Mean Time, the observed Altitude of the Sun's L.L. was 16° 51′ 50′′, and again P.M. the same day, when the Chronometer showed 17d 11" 15m 36s Greenwich Mean Time, the observed Altitude of the Sun's L.L. was 12° 9' 2", the ship having made 27 miles on a true W. S. course in the interval, Height of Eye 12 feet. Required the line of position when the first Altitude was taken; also the bearing of the Sun, and the position of the ship by Sumner's Method when the second Altitude was observed, the ship being supposed to be between the parallels of 45° 55′ N. and 46° 15′ N.

IO. If at sea on October 20th, 1885, P.M., and uncertain of my position, when the Chronometer showed 20d 3" 45"15" Greenwich Mean Time, the observed Altitude of the Sun's L.L. was 24° 38′ 50′′, and again P.M. the same day, when the Chronometer showed 20d 5h 20m 185 Greenwich Mean Time, the observed Altitude of the Sun's L.L. was 12° 21′ 53′′, the ship having made 25 miles on a true North course

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