28 



REPORT ON 



In a few instances true bearings were obtained by observing the sun when its 

 apparent elevation above the horizon was equal to its diameter. In that case 



£ = 90° 



and then 



cos A = 



sin 8 



COS<^> 



in which the azimuth will be north or south of the prime vertical according as the 

 sun's declination is north or south. 



Observations of the Sun, made October j,\st, 1865, to determine the true bearing of the object used as 

 an azimuth mark in swinging the ship at Hampton Roads, Va. 





io h io m 50 s 



" 45 

 12 15 

 14 

 14 39 



a 



s 

 c 



r 



a 



b nearly 



C 



127° 20' 

 38 

 45 



128 4 

 8 



T 



Chronometer fast 



10 12 42 



4 50 



4- 16 16 



127 47 

 + 16 

 + 16 



Apparent time 



10 24 8 



128 19 



t 

 S 



9 



M 

 $ — M 



23° 58' 

 — 14 16 



36 58 



— 15 33 



52 31 



55 59 



— 1 



55 58 

 90 

 138 26 



True bearing of sun S. 28° 21' E. 



Z Seminary to sun . . . . . . . . 138 26 



Z Seminary to Rip Raps . . . . . . . 62 44 



Z Rip Raps to tree . . . . . . . . 114 37 



True bearing of tree S. 10 34 W. 



Observations of the Sun, made November 18th, 1865, to determine the true bearing of the object used 

 as an azimuth mark in swinging the ship at St. Thomas, West Indies. 





7 " o m 5 8 

 2 15 

 4 45 



8 15 



9 45 



a 



w 



s 

 c 



r - 



r 



a 



b nearly 



C 



34° 13' 

 15 

 10 

 12 

 12 



T 



Chronometer slow 



7 5 1 



40 47 



+ 14 3 6 



34 12 

 + 16 

 + 16 



Apparent time 



8 24 



34 44 



t 

 S 



M 



q> — M 



59° 54' 



— 19 19 

 18 20 



— 34 57 

 53 i7 



69 48 

 — 2 

 69 46 

 90 

 28 52 



True bearing of sun 

 Z Sun to Peak 



S. 6o° 27' E. 



28 52 



True bearing of Peak . S. 31 35 E. 



