Astronomical and Nautical Collections. 



107 



Example III. 



July 1, 1824, in N. latitude, at 9" P.M., the true altitude of the 

 sun's centre was 13° 30'; and on July 2, at 2" 32" A.M. his alti- 

 tude was 11°; required the latitude, the mean declination being 

 23° 5'. 



To find arc I. 

 1. cos. D' = 9.963757 

 1. sin. i E = 9.821265 

 37° 33' 30" 9.785022 1. s. 



I = 75 7 



To find arc II. 

 1. sin. E = 9.996751 

 1. cos. D = 9.963782 

 1. cosic. I = 0.014820 

 70° 52' 44" 9.975353 1. s 



II =35 26 22 



To find arc V. 



I. cos. A = 9.987832 



1. cos, D == 9.963732 



2.1. sin. IV = 7.972322 



const, log. = 0.301030 



N = 16785 8.224916 

 n. cos. aTd =~986021 

 - N 16785 



Lat. = 75° 45' 4" 969236 n.s 



To find arc III. 



1. cosec. I = 0.014820 



1. sec. A = 0.012168 



1. cos, |.b + a = 9.809793 



1, sin. |.s'-^= 9.797071 



2) 19.633852 



III = 40° 59' 53" 9.8169'2"6'l. s, 

 II =35 26 22 



IV c= 5 33 31 



I =: 75 7 

 A = 13 30 



I , S + a=:49 48 30 

 j . S-a = 38 48 30 



In this example the first observation is taken in the afternoon, 

 and the second in the forenoon ; therefore the fourth arc is equal 

 to the difference of the second and third arcs, by Rule 11. 



