THERMOMETRICAL OBSERVATIONS. 201 



for the correift apparent time. The longitude of the place of obfervation 

 was eftimated at 5'' 39' weft from Greenwich. From the latitude of the 

 place, tlie apparent time of the obfervation, and the eftimated longitude, 

 the true altitude of the ]) 's centre comes out 64° 53' 52" and that of the 

 ©'538° 14' 50" — from which the longitude will be had as follows : 



1) 's true altitude 

 O's do. 



Difference true altitudes 



J 's apparent altitude 



©'s . do. . . . 



Difference apparent altitudes 

 Apparent dift, I 's and ©'s centres 



Sum . , . . . 



Difference 



4 Sum . . . . . 



4^ Difference . . . . 



5 's apparent altitude 



2) 's true altitude 

 ©'s apparent altitude 

 ©'s true altitude 



Difference true altitudes 

 4- Diflference true altitudes 



64 53 52 

 38 14 50 



50 45 3 

 24 31 I 



64 29 58 CO. or 



64 53 52 . 



'38 I J 56 CO. or 



38 14 JO 



26 39 2 

 13 19 3' 



67 43 46 



67 45 46 



37 27 22. J 

 2 



S 9.8889664 



S 9.6180087 



c. S 0.3660068 



S 9.6276060 



c. S 0.1050480 



S 9.8950616 



2)39.5006975 



19-750.3487 

 S 9.3626315 



T' 10.3877172 



c. S 9.5786170 



S 9.7840145 



True diftance . . . . 74 54 45.0 



Dift. at Greenwich at noon the 23'' o'' 76 14 17 

 Do. . . . 23 3 74 45 57 



Difference between the ift and 2d 

 Do. between the 2d and 3d 



1 19 32 



1 28 20 



P. L. 

 P. L. 



3547 

 3091 



0456 = 2^ 42' 4" 

 which 



