London, Hodgson & Son, 1950. Royal 8vo. Volume 51 of "Proceedings of the London Mathematical Society. Second Series" Bound with all the six original front-wrappers for all six parts of the volume (bound in at rear) in a very nice contemporary blue full cloth binding with gilt lettering and gilt ex-libris ("Belford College. Univ. London") to spine. Minor bumping to extremities. Binding tight, and in excellent, very nice, clean, and fresh condition, in- as well as ex-ternally. Small circle-stamp to title-page ("Bedford College for Women"). Discrete library-markings and book-plate stating that the book was presented to the Library of Bedford College by "Professor H. Simpson./ 1949-50" to pasted-down front free end-paper. Library-label tipped in at front free end-paper. Pp. 161-175. [Entire volume: (4), 483 pp.].
First edition of one of the last articles by a key figure in Map-colour theory.
Percy John Heawood, proved in 1890 that Alfred Kempe's Four-colour theorem was flawed and established his own five-colour theory.
"Heawood was, however, able to salvage an important idea, that of Kempe chains, from Kempe's proof. Using Kempe's work, Heawood was able to prove that every map is 5-colorable." (Hilton, Mathematical vistas: from a room with many windows, 2002, p. 148 ).
"It is not known how Heawood became aware of the Four-Color problem. However, his life's work in mathematics was centered on it. After his first paper, 1890, he published seven more papers on the same subject, the last in 1949 at the age of 88.", his biographer Gabor Dirac wrote. (Fritsch, Rudolf. The four color theorem: history, topological foundations, and idea of proof, 1998, 24 p).
Order-nr.: 42736