Paris: Gauthier-Villars, 1912. First Edition. paperback. Avec une preface de Giuseppe Peano. Illustrated with 14 diagrams. 106 pages. Tall thin 8vo, original brown printed wrappers, uncut edges (wrappers are somewhat worn and darkened at edges; one corner chipped; neatly inked name on blank flyleaf. Paris: Gauthier-Villars, 1812. First edition. Very good. very good.