132 Mr WALLACE, ON GEOMETRICAL THEOREMS, AND FORMULAE. 



sm{(}) = xb) 9-6106802 tan 9-6202062 



sm{f = xc) 9-9849774 sin(</) + x//) 9-9945029 



9-6257028 96257033 



The near agreement of the logarithms shews that the angles (p, ■>// are 

 determined with sufficient accuracy. 



The angles of the triangles are as below: 



We may now find i/ and si for the computation of which we have 

 all the logarithms. 



y= 11124-25 40462706. » = 7733-484 3-8883753. 



From what has been done in this paper, it is manifest that the 

 Geodetical problem which has suggested it may be resolved in a great 

 variety of ways. Probably the solution by the Angular Calculus will 

 be the most convenient in practice. 



32. There is a geodetical problem akin to that which has been 

 here so fully discussed, to which the propositions delivered in this 

 paper apply elegantly. It is this: 



" Given the elevation of an object above a plane as observed at 

 three stations in that plane whose positions are known; to find the 

 place of the object reduced to the plane." 



