Geometry of Four Dimensions

Contents: The Foundations Of Four Dimensional Geometry; Points And Lines; Triangles; Planes; Convex Polygons; Tetrahedrons; Hyperplanes; Convex Pyramids And Pentahedroids; Space Of Four Dimensions; Hyperpyramids And Hypercones; Perpendicularity And Simple Angles; Angles Of Two Planes And Angles Of Higher Order; Symmetry, Order, And Motion; Euclidian Geometry; Figures With Parallel Elements; Measurement Of Volume And Hypervolume In Hyperspace; The Regular Polyhedroids; The Polyhedroid Formula

Published September 1914