MAGNETIC OBSERVATIONS. 



29 



Observations of the Sun, made Novem. er 28//?, 1865, to determine the true bearing of the object used 

 as an azimuth mark in swinging the ship at Isle Royal, Salute Islands. 





6 h 27™ 

 28 

 3i 



5" 



59 



8 



a 

 s 



c 



r 



a 



b nearly 



C 



74° 5°' 

 46 

 40 



T 



Chronometer slow 



* 



6 29 



1 3° 



+ 11 



4 

 19 

 45 



74 45 

 + 17 

 + 16 



Apparent time 



8 n 



8 



75 18 



8 



■!> 

 M 



57° 



— 21 



5 



— 35 

 4i 



l 3' 



22 



17 



52 

 9 



62 4 

 — 2 

 62 2 

 90 

 73 18 



True bearing of sun 

 L Sun to Nob . 



S. 62 24' E. 



73 18 



True bearing of Nob S. 10 54 W. 



Observations of the Sun, made December 1 2th, 1 865 , to determine the true bearing of the object used 

 as an azimuth mark in swinging the ship at Ceara, Brazil. 



1 



t n ra 8 s 



13 



14 32 



a 



s 

 c 



f 



r 



a 



b nearly 



C 



87° 30' 

 22 

 21 



T 



Chronometer slow 



■t 



3 12 53 

 2 26 32 



+ 5 47 



87 24 

 + 16 

 + 16 



Apparent time 



5 45 12 



87 56 



t 

 8 



M 



$ — M 



86° 18' 



— 23 8 



— 3 43 



— 81 25 

 77 42 



85 4 

 — 18 

 84 46 

 90 

 87 56 



True bearing of sun 

 Z Lantern to sun 

 L Light-house to Lantern 



S. 67 3' W. 

 87 56 

 77 o 



True bearing of Light-house . . . . . . N. 82 7 E. 



Observations of the Sun, made December 29///, 1865, to determine the true bearing of the object used 

 as an azimuth mark in swinging the ship at Bahia, Brazil. 



When the sun's true zenith distance was about 90°, the angle between its nearest limb and a con- 

 spicuous tree was measured and found to be 31° 38', the tree being to the right of the sun. 

 $> = — 12° 59' 8 = — 23° 12' 



True bearing of sun S. 66° 9' W. 



I_ Sun to tree ......... 31 38 



Sun's semi-diameter ....... o 16 



True bearing of tree N. 81 57 W. 



