271 



Concerning Spheric Geometry. 



Ey David A. Roth rock. 



(Abstract.) 



In this pajior is develoi)od a system of analytic fjeometry npon the 

 surface of a spliere, in wliich the axes of reference are great circles and 

 the coordinates of a point are arcs of great circles. With a proper choice 

 of axes, the equations of the loci known as spheric straight line, spheric 

 circle, spheric ellipse, spheric hyperbola, spheric parabola defined metri- 

 cally as in plane analytics, appear in a form analogous to their equations 

 in the plane. 



The paper also investigates other loci of more complex character, to- 

 gether with a discussion of the notion of spheric pole and polar, radical 

 axis, etc. A summary of the literature upon this system of geometry is 

 also included. 

 inooniington, Indiana, 

 ^^or ember 30, IDll. 



