1950. Fourth Edition. 154 pages. Blue dust jacket over brown cloth. Pages are lightly tanned and foxed throughout. Cracking to hinges with exposed binding. Binding remains firm. Boards have mild edge wear with slight rubbing to surfaces. Soft crushing to spine ends. Light tanning to spine and edges. Unclipped jacket has heavy edge wear with some areas of loss, heavy tears, chips and creasing. Mild tanning to spine and edges. Scuffing and light marking overall.