230 



Ocean Magnetic Observations, 1905-16 



Geographic Positions at Sea: Latitude and Longitude Observations {Two-Star Altitudes) 



(Form 41a) 

 Date: Sat., Aug. 23, 1913, P. M. Vessel: Carnegie Com'd'T: W. J. P. Obs'r: H. R. S. Computer: H. R. S. 



Object 



Arcturus 



Means 

 Corrections 



G. M. T. 

 R. A. M. S. 

 Tab. Ill 



G. S. T. 



R. A. of star 



H. A. from Gr. 



Sex. No. 2944 



Total 

 Corr'd latitude: 39° 47:8 N 



Time by 

 Watch M 



m s 



45 56 



46 27 



46 48 



47 05 

 47 28 

 47 53 



9 46 

 +01 



56.2 

 19.8 



48 

 04 

 01 



16.0 

 41.3 

 36.6 



19 54 33.9 

 14 11 43.1 



5 42 50.8 



Observed 

 Altitude 



46 

 46 

 46 

 45 

 45 

 45 



09.5 

 04.0 

 00.5 

 57.0 

 52.0 

 47.5 



45 58.4 

 -01.9 



Chron'r 53862 

 Chron'r corr'n 

 G. M. T. 

 Watch M 



Watch M corr'n 



Starb'd log . 

 Port log . . . 



Chronometer Comparisons 



Before 



m s 



04 35.0 

 +36.5 



05 11.5 

 03 52.0 



+01 19.5 



After 



m a 



58 25.0 

 +36.5 



59 01.5 

 57 41.6 



+01 19.9 



45 

 39 

 70 



56.5 

 47.1 

 22.0 



156 05.6 

 78 02.8 



= True h 

 = ^ 



= V 

 = 2s 



32 06.3 = is-h) 



Corrections to Obs. Alt. 



Semi-diameter 

 Refraction and Par. 

 Dip of horizon 

 Index corr'n 

 Eccentricity 



-0.9 

 -3.5 



+2.5 



-l.t 



Log see ip 

 Log CSC /) 



Log cos s 



Log sin (s-h) 

 Log sin' \l 



H. A. from Gr. 

 Longitude in time 

 Longitude in arc 

 Corr'n for ass'd lat. (+0'.7) 



(+0.3) 

 Corr'd longitude 



0.11438 

 0.02601 



9.31621 

 9.72548 



9.18208 



m s 

 03 37.5 

 42 50.8 

 39 13.3 

 39° 48'.3 



+00.2 

 39 48 . 5 



Astronomic Elements 



Decl'n at G. M. N. 

 Hourly diff.: O'.O 

 Time from G. M. N. 



+9 "8 

 Corr'n: (+9.8) (0.0) 



Decl'n at obs'n 



Eq. timeatG. M. N. 



Hourly diff.: 



Time from G. M.N. : 



Correction: 



Eq. time at obs'n 



R. A. of star at G. 



M. N. 

 Hourly diff.: O'O 

 Time from G. M. N.: 



+9^8 

 Corr'n: (+9.8) (0.0) 



Right ase'n at obs'n 



+ 19 38.0 



0.0 



+ 19 38.0 



for Sun 

 obs'ns 



h m 3 

 14 11 43.1 



00.0 



14 11 43.1 



Remarks 

 Position: quarter-deck 

 Ht. ofeye: 13 ft. Horizon: good 

 Wind: SSW Bar.: 772 mm. 



Thermometer; 24?4 C. 

 Direc. of obj.: N 103° W 



Object 



Jupiter 



Means 

 Corr'ns 



G. M. T. 

 R. A. M. S. 

 Tab. Ill 



G. S. T. 



R. A. of star 



H. A. from Gr. 



Sex. No. 2944 



Total 

 Corr'd latitude:' 39° 47'.8 N 



Time by 

 Watch M 



h 

 9 



m s 



53 26 



54 07 

 54 28 



54 48 



55 06 

 55 25 



9 54 

 +01 



33.3 

 19.9 



9 55 53.2 



10 04 41.3 



+01 37.9 



20 02 12.4 

 18 35 51.8 



1 26 20.6 



Observed 

 Altitude 



24 



31, 

 34 

 36 

 38 

 39 

 40 



24 36.8 

 -03.1 



Chron'r 53862 

 Chron'r corr'n 

 G. M. T. 

 Watch M 



Watch M corr'n 



Starb'd log 44.1 

 Port log 



Chronometer Comparisons 



Before 



m s 



04 35.0 



+36.5 



05 11.5 

 03 52.0 



+01 19.5 



After 



h m s 

 9 58 25.0 

 +36.5 

 9 59 01.5 

 9 57 41.6 



+01 19.9 



24 33 . 7 



39 47.1 



113 23.7 



177 



88 



44.5 

 52.2 



True h 

 V 



2s 



5 



64 18.5 = {s-h) 



Corrections to Obs. Alt. 



Semi-diameter 

 Refraction and Par. 

 Dip of horizon 

 Index corr'n 

 Eccentricitv 



-2.1 

 -3.5 



+2.5 



-3.1 



Log sec ¥> 

 Log CSC p 



Log COS s 

 Log sin (s-K) 

 Log sin* \l 



t 



H. A. from Gr. 



Longitude in time 



Longitude in arc 



Corr'n for ass'd lat. (+0'.7) 



(-4.0) 

 Corr'd longitude (West) 



0.11438 

 0.03726 



8.29492 

 9.95479 



8.40135 



h m s 



1 13 04 . 1 



1 26 20.6 



2 39 24.7 

 39° 51 '.2 



-02,8 

 39 48.4 



Astronomic Elements 



Decl'n at G. M. N. 

 Hourly diff.: -O'.Ol 

 Time from G. M. N.: 



+9 9 

 Corr'n: (+9.9)(-0.01) 



Decl'n at obs'n 



Eq. timeatG. M. N. 



Hourly diff. : 



Time from G. M. N. : 



Corr'n: 



Eq. time at obs'n 



R. A. of star at G. 



M. N. 

 Hourly diff.: -0»41 

 Time from G. M. N.: 



+9''9 

 Corr'n: (+9.9)(-0.41) 



Right asc'n at obs'n 



-23 23.6 



-0.1 



-23 23.7 



for Sun 

 obs'ns. 



h m a 

 18 35 55.9 



-04.1 



18 35 51.8 



Remarks 

 Position: quarter-deck 

 Ht. of eye: 13 ft. Horizon: good 

 Wind: SSW Bar.: 772 mm. 



Thermometer: 24?4 C, 

 Direc. of Obj.: N 162° E 



