"An admirable introduction to the rigorous theory of the continuum."--Science Progress "Extremely readable . . . a clear axiomatically constructed introduction."--Elemente der Mathematik This classic of mathematics presents the best systematic elementary account of the modern theory of the continuum as a type of serial order. Based on the Dedekind-Cantor ordinal theory, this text requires no knowledge of higher mathematics. Contents include a historical introduction and chapters on classes in general; simply ordered classes, or series; discrete series, especially the type of the natural numbers; dense series, especially the type of the rational numbers; continuous series, especially the type of the real numbers; continuous series of more than one dimension, with a note on multiply ordered classes; and well ordered series, with an introduction to Cantor's transfinite numbers. 1917 edition. 119 footnotes, mostly bibliographical.