Some types of Q-surfaces in a rectilinear congruence produced by circular transformations (1914)
Stokes, Claude Newton, 1890- · leaf 51
ver the circle C , let P.,B, P<be any setof points on it and A,A«,A*and A, A^Ajbe their inversions on theplanes, then there is plainly a projective relation existing between(Z.A A/A* ) and (Z.aa/A*) and consequently (A A, Aa ) ^(aaa^), thenby the quality ascribed to two projective ranges of… … congruence which is tangent to the conic k which lies in a planepassing through zzand the point. When the conic is turned about ZZ,k being variable, a certain surface Q is generated. Wow since alllines of the congruence pass through ZZ, the congruence in the mainconsists of all lines passing…
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