1942. Reprint. 124 pages. No dust jacket. Blue cloth with gilt titles to front and spine. Part I. Advisory editor E W Knott. Includes various diagrams. Pages have slight foxing, tanning and minor thumbing. A few dog-eared corners. Faint creases to some pages. Slight staining to pastedowns. Boards have some moderate edge wear, with slight bumping to corners and minor bumping to spine ends. Spine is heavily sunned. Strips of heavy sunning front and rear. Gilt is dulled and worn.