1950. 4th Edition. 179 pages. Blue dust jacket over blue cloth. Binding remains firm. Pages are lightly tanned throughout. Top corner of front free endpaper cut out. Pencil inscription to rear pastedown. Boards have light shelf-wear with corner bumping. Slight crushing to spine ends. Light sunning to edges. Unclipped jacket has moderate edgewear with chips, tears, and creasing. Small areas of loss to spine ends. Light tanning to spine and edges.