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observation was taken, the ship's position being by account lat. 6°4'S.: long. 115° 1'E.

13. Dec. 12th, 1854, the following double altitude of the sun was taken:

app. time at ship. obg. alt. O
12d ob 20- 12*

59° 24' 9" bearing N.21°E. 12 4 0 12

35 57 26 the course and distance in the interval, N. 33°W. 28 miles : eye, 19 feet: required the true latitude when the second observation was made, the ship’s position at the time being by account, lat. 52° 58'S.: long. 60° 3'E.

:

14. Feb. 19th. 1854, A.M. at ship: lat. 6° 4'S.: the following lunar observation was made :obs. alt. O

obs. alt. Ő obs. dist. near limbs. 41° 36'0" 26° 56' 30"

108° 5' 40" index err. +14

0

-35 eye, 25 feet : time by chronometer, 18d 13h 2m 50“, which was supposed to be 17" 68 elow on mean time at Greenwich : determine the error of the chronometer on mean time at Greenwich by lunar: also the longitude.

15. Nov. 15th 1854 : A.M. at ship: lat. 39° 50'N. the following obscrvations were made : obs. alt. O obs. alt.

obs. dist. n.ls. 22° 26' 30" 52° 14' 40"

59° 46' 0". index error + 12

20 eye 16 feet: time by chronometer 154 15 0m 58", which was supposed to be 48m 11.58 slow on mean time at Greenwich : required the error of the chronometer on Greenwich mean time by lunar, and the longitude.

+ 10

16. May 9th, 1854, at 8h 36m P.m. by watch at ship: lat. 8° 26' S:: long. by account, 107° 42'W. obs. alt. Pollux, W. of mer.

obs. alt. ) obs.dist. (n. 1. &* 19° 30'

69° 15' 20" 84° 17' 20"
0
1 16

+9 eye, 17 feet: required the true longitude.

index error

:

17. Feb. 6th, 1854 : at 5h 20m 46' P.m. by watch at ship: lat. 50° 13'N. : long. by account, 22°W.: obs. alt. Venus (centre)

obs. dist: ( n.l. and W, of mer.

obs. alt

Venus centre 24° 26'0"

51° 59' 0" 80° 9' 10" +32

- 15

ind. err.

+41

eye, 25 feet : required the true longitude.

:

18. Feb. 12th. 1854: at 10h 2m 28 P.M. by watch at ship: lat. 4° 16'S : long. by ac. 131° 47' E. obs. alt Saturn (centre) W. of mer.

obs alt. r obs. dist. n.l.& h 27° 37' 0" 52° 17' 10"

82" 4' 15" index error + 41

3

- 18 eye 21 feet: required the true longitude.

+ 1

19. Sept. 3rd, 1854: at 7" 40" 28 P.M. by watch at

" ship: lat. 46° 30'S: long. by account 90° 40'W. obs. alt. Fomalhaut E. of mer.

obs. alt. ( obs. dist.(f.1. & * 38° 34' 50" 57° 43' 30"

33° 7' 10" -20 +17

3 eye 23 feet: required the true longitude.

ind. err.

+1

20. A ship by dead reckoning has made S. 7° W. 100 miles, but by observation it is found to have made S. 50° E. 94 miles, reqriired the set and drift of the current.

21. A ship by dead reckoning has made N. 69° E. 82 miles, but by observation it is found to have made S. 65° E. 101 miles, required the set and drift of the current.

22. A ship by dead reckoning has made E. 75 miles, but by observation it is found to have made N.63° E. 78 miles, required the set and drift of the current.

23. A ship by dead reckoning has made N.30°W. 105 miles, but by observation it is found to have made N. 20° W. 101 miles, required the set and drift of the current.

Paper I. 1. Jan, 7, 1854 : P.M. at ship: lat. 40° 36'S.: obs. alt. O

obs. dist. O & ( n.ls. 35° 29' 50"

108° 5' 40" -18

+14 eye 27 feet: time by chronometer 7d 6 20" 2*, which was supposed to be 20m 28 fast on mean time at Greenwich : required the longitude, and error of chronometer on Greenwich mean time, by lunar observation.

index error

2. Feb. 17th 1854 : A.M. at ship: approximate latitude, 39°: long. 166o 30 E.: observed meridian altitude ( 50° 10' 40": (S. of observer: index error +1'2": eye 18 feet: required the true latitude.

3. March 20th, 1854: at 7h 17m P.M. mean time at ship: longitude 19° 56'W.: the observed altitude of Polaris off the meridian being 54° 50' 40": index error +1' 10": eye 23 feet : required the latitude.

4. April 2nd, 1854: the following observations were made for latitude, by double altitudes, app. time at ship,

obs. alt. O 8h 16m 44%A.M.

31° 24' 13" bearing E. by S. 1S. 11 1 44 A.M.

61 0 20 eye 22 feet: course and distance in the interval S. AE. 28 miles : lat. by account 30° 2'N.: long. 171° 11'E.: required the true latitude, when the second observation was made.

4a. Verify the above by Sumner's method.

5. April 15th, 1854: lat. 16° 50'N.: long. 99° 52'W.: equal altitudes of the sun's lower limb being observed, when the corresponding times by chronometer were 15d 3h 50m 40s and 154 gh 20m 40°: determine the error of the chronometer for apparent and mean time at the place of observation, and also on mean time at Greenwich.

6. April 27th, 1854: the observed altitude of the sun's lower limb, in an artificial horizon, being 61° 15' 40": index error, -2' 10": required the true altitude of the sun's centre.

7. A ship by dead reckoning has made S.44°E. 97 miles, but by observation she is found to have made S. 11°W. 101 miles : determine the set and drift of the current.

Paper II. 1. May 11th 1854: at 9h 48m 31° P.M. mean time by watch at ship: lat. 38° 40'S. : long. by ac. 171° 6'E.: the observed distance of Regulus (a Leonis; and i's near limb being 65° 50' 30": index error +1' 16": required the true longitude.

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2. May 10th, 1854, approximate latitude 55° : long. 86° 15'E. observed meridian altitude ( 40° 10'30": observer S. of ( : eye, 24 feet : required the true latitude.

3. May 15th, 1854, at 114 om 50$ P.M. mean time at ship: long. 30° 40'W.: the observed altitude of Polaris off the meridian, being 49° 58' 40": index error —50": eye 22 feet: required the latitude.

:

4. May 28th, 1854 : the following observations were made for latitude by double altitudes, app. time at ship.

obs. alt. O 280 oh 58m 30%

66° 41' 11" bearing N.W. 28 3 29 42

35 44 0 eye 18 feet: the course and distance in the interval S.S.W.14 miles: lat. by ac. 3° 7'N. : long. 2° 15'W.: required the true latitude when the second observation was taken.

4a. Verify the above by Sumner's method.

5. May 16th, 1854: lat. 20° 28'S. : long. 28° 51°W.: equal altitudes of the sun's lower limb being observed, when the corresponding times by chronometer were 15d 23b 5m 30and 164 4h 52m 10%, required the error of the chronometer on apparent and mean time at the place of observation, and also on mean time at Greenwich.

6. May 24th, 1854: the observed meridian altitude of the sun's lower limb in an artificial horizon being 97° 43' 50”: index error + 1' 20": required the true altitude of the sun's centre.

7. A ship by dead reckoning, makes N. by E. 106 miles, by observation she is found to have made N.N.W. 100 miles ; determine the set and drift of the current.

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