Proceedings of the Edinburgh Mathematical Society

arithmetic axes bisect body centrode centre of inversion centre of similitude cercle chord circonférence circumscribed circle collinear common tangent conique curve density deux diameter distance draw droite Edinburgh EDINBURGH MATHEMATICAL SOCIETY ellipse equation equiangular polygon equilateral polygon equilateral triangle Euclid figure fluid foyer F geometrical GEORGE THOM given aperture given circle given point given straight line given triangle greater Hence inscribed and circumscribed intersect Join l'angle l'axe radical le point medians middle point minimum numbers n-gon nine-point circle number of sides parallel pericyclic perpendicular plane polaire problem progression quadrilateral radical axis radius rapport rectangle of inversion right angle similar space centrode square supposed Take any point tangent term theorem transformation triangle ABC triangle whose sides valeur velocity vertices vortex vortices W. J. MACDONALD δε σ δρ