APPENDIX. 

 " the diflance. This I have endeavoured to facilitate by 

 *' the following problem, which may be applied to any 

 " zodiacal ftar, and will be of ufe when the ftar fet down 

 " in the Ephemeris cannot be obferved. 



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cc 



PROBLEM. 



" Having given the diftance of two objeds near the 

 " ecliptic, with their latitudes, to find their difference of 

 " longitude. 



"SOLUTION. 



" Find an arc A, whofe logarithmic fine is the fum of 

 " the logarithms of the fines of the two latitudes and the 

 *' logarithmic tangent of half the diflance, rejeding twenty 

 " from the index of the fum. 



" Find an arc B, whofe logarithmic fine is the fum of 

 " the logarithmic verfed fine of the difference of latitude, 

 " and the logarithmic cotangent of the diftance, rejeding 

 *' ten from the index of the fum. 



*' Then A added to the obferved diftance, and B fub- 

 " traded from the fum, leaves the difference of longitude. 



" If one of the latitudes is South, and the other North, 

 " the fum of the two arcs A and B fubtraded from the 

 *' diftance, leaves the difference of longitude. 



Mm "EXAMPLE. 



