PAPER VII.-Continued.

1884. July 10th. Find the time of high water at Hastings, A.M. and P.M.

1885. September 1st at 5h 37" P.M., apparent time at ship in lat. 33° 49' S.; long. 151° E.; the sun's observed amplitude was NW by W. Required the True Amplitude and Error of the Compass; and supposing the variation to be 24° W., required the Deviation.

1885. July 20th, P.M., at ship in lat. 10° S.; the observed altitude of the sun's lower limb was 23° 56' 10"; height of eye 15 feet. Time by a chronometer July 20d 14h 16m 103, which was correct for Greenwich Mean Time on May 19th at noon, and losing 4.2° daily. Required the Longitude.

ADDITIONAL FOR ONLY AND FIRST MATES.

1885. July 6th, A.M., Mean Time at Greenwich 5 21h 31 os, in lat. 51° 30' N.; long. o.; the sun's bearing by compass S 60° 40' E.; observed altitude of sun's lower limb 48° 27' 30"; height of eye 20 feet. Required the True Azimuth and Error of the Compass; and supposing the variation to be 21° 30′ W., required the Deviation.

1885. November 16th, A.M., at ship, lat. by account 51° 57' S.; long. 12° W.; the observed altitude of the sun's lower limb 56° 29′ 20′′ North of the observer; height of eye 17 feet. Time by chronometer 15a 23h 33m 43o, which was 39 20s slow on Mean Time at Greenwich. Required the Latitude by the Reduction to the Meridian.

ADDITIONAL FOR MASter.

1885. September 10th; the observed meridian altitude of the star "a Ophiuchi," bearing North, was 77° 24′ 50′′; height of eye 15 feet. Required the Latitude.

Find the Index Error and the Sun's Semidiameter from the following readings of the Sextant: 31′ 15′′ on and 30' 40" off.

K

NAPIER'S DIAGRAM.-PAPER VII.—Continued.

ADDITIONAL FOR MASTER.

In the following Table give the correct magnetic bearing of the distant object, and thence the deviation.

CORRECT MAGNETIC BEARING:

With the deviation as above, give the courses you would steer by the standard compass to make the following courses, correct magnetic

Correct magnetic courses N E by N., W SW I W.,
SE by E.

Compass courses

Suppose you have steered the following courses by the standard compass, find the correct magnetic courses made from the above deviation table.

Compass courses S W., N N E., E § S.
Magnetic courses

You have taken the following bearings of two distant objects by your standard compass as above; with the ship's head at S E., find the bearings, correct magnetic.

Compass bearings N 6° E., E § S.
Bearings, magnetic

SUMNER'S METHOD.

FOR MASTER, FIRST MATE, AND ONLY MATE. If at sea on May 16th, 1885, A.M., and uncertain of my position, when the chronometer showed 15d 17h 26m o Greenwich Mean Time, the observed altitude of the sun's L.L. was 47° 55′ 40′′, and again P.M. the same day,

PAPER VII.-Continued.

when the chronometer showed 15d 22h 32m 58s Greenwich Mean Time, the observed altitude of the sun's L.L. was 46° 1′ 51′′, the ship having made 27 miles on a true N W. 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 49° 10' N. and 49° 40' N.

FOR MASTER, FIRST MATE, AND ONLY MATE.

Magnetic Chart.

1. Using deviation card No.

find the course to steer by compass from E to O (the centre of the compass), also the distance.

2. With the ship's head on the above-named compass course, a [point] [lighthouse] F bore by compass N 4° 36' W. and D bore N 34° 46′ E by the same compass. Find the ship's position.

3. With the ship's head as above, a [point] [lighthouse A bore by compass S 46° W., and after continuing on the same course 15 miles, it bore S 1° W. Find the ship's position, and her distance from A at the time of taking the second bearing.

ADDITIONAL FOR MASTERS.

4. Find the course to steer by compass from E to O (See Question 1.) to counteract the effect of a current, which set N W by W W. (correct magnetic) at the rate of 4 miles per hour, the ship making by log 8 miles per hour; also the distance the ship will then make good in 7 hours towards O.

5.-On December 3rd, 1884, at 10" A.M., being off Lundy Island, by reckoning took a cast of the lead. Required the correction to be applied to the depth obtained by the lead line before comparing it with the depth marked on the Chart.

PAPER VIII.

(Second Mate as far as Longitude by Chronometer.) Multiply 12344 by 57 by common logarithms. Divide 27.616 by 6.904 by common logarithms.

H. Courses. K. TO Winds. L. Deviation.

Remarks.

115° 0' W. A point lat. 2° 10′ N., long. 0° 38′ E., bearing N.N.E. by com

pass, distant 10 miles. Ship's head S.W. Deviation 15° W.

1885. September 1st, in long. 97° 12' E.; the observed meridian altitude of the sun's lower limb was 51° 1′ 50′′ bearing South; index error -5′; height of eye 21 feet. Required the Latitude.

In lat. 2° 10' N. the departure made good was 210 miles. Required the difference of longitude by parallel sailing.

Required the course and distance from A to B on Mercator's principle.

Lat. of A 56° 30' S.
Lat. of B 33 30 N.

Long. of A 47° 13′ W.
Long. of B 42 47 E.

PAPER VIII.—Continued.

1884. August 21st. Find the time of high water at Ayr, A.M. and P.M.

1885. July 12th, at 5h 42" A.M., apparent time at ship in lat. 11° 31' N.; long. 16° 52' W.; the sun's observed amplitude was E. by N. Required the True Amplitude and Error of the compass; and supposing the variation to be 20° W., required the Deviation.

1885. October 3rd, A.M., at ship in lat. 10° S.; the observed altitude of the sun's lower limb was 41° 51′ 50′′; height of eye 15 feet. Time by a chronometer October 2d 16h 10m 153, which was correct for mean noon at Greenwich on July 31st, and on October 2nd it was 1m 35 slow on mean noon at Greenwich. Required the Longitude.

ADDITIONAL FOR ONLY AND FIRST MATES.

1885. July 1st, mean time at ship 9h 8m 32 A.M., in lat. 30° 20' N.; long. 70° 20' W.; the sun's bearing by compass E N.; observed altitude of the sun's lower limb 50° 18' 0"; height of eye 14 feet. Required the True Azimuth and Error of the compass; and supposing the variation to be 16° 15′ W., required the Deviation.

1885. June 10th, P.M., at ship, lat. by account 15° 7' S. long. 96° 35' E.; the observed altitude of the sun's lower limb was 51° 20' 50" North of the observer; height of eye 14 feet. Time by watch 9d 18h 15m 40s, which was found to be 6h 2m 51 slow of apparent time at ship; the difference of longitude made to the Eastward was 18 miles after the error on apparent time at ship was determined. Required the Latitude by the Reduction to the Meridian.

ADDITIONAL FOR MASTER.

1885. July 25th. The observed meridian altitude of the star "Markab" bearing South was 53° 8' 20"; height of the eye 14 feet. Required the Latitude.