52 KEV. HUGH MARTIN ON TRILINEAR CO-ORDINATES. 



anapole of inverse points is the pole of the line joining them — to the same 

 imaginary conic. 



Theorem LXX. 



If one of two points remain fixed and the other move in any manner what- 

 ever, the locus of the anapoles is a straight line. 



Theorem LXXL 



If two points move away from each other along a straight line with uniform 

 velocities, their anapole will describe a conic section ; and if the uniform veloci- 

 ties be equal, a straight line. 



Theorem LXXII. 



The anapole of any two points in a conic section passing through the angles 

 of the triangle of reference is invariable, and its co-ordinates are proportional to 

 the sides of the triangle. 



