DETEKMINATION OF ELLIPTIC ORBITS. 



131 



Preliminary computations relating to the second and third 



observations. 



The formulae are entirely analogous to those relating to the first 

 observation, the quantities being distinguished by the proper suffixes. 



III. 



Equations of the first hypothesis. 



When the preceding quantities have been computed, their numerical 

 values (or their logarithms, when more convenient for computation,) 

 are to be substituted in the following equations : 



Components of @i 



nil 



For control : 



For control 



ry, __ 

 ~ 



Components of @' 



Components of 



y 2 = _ 2 - 



Components of @" 



IIL 



