1950. Fifth Edition. 515 pages. No dust jacket. Red cloth with black and white illustrations and fold out diagrams throughout. Moderate tanning to pages with heavier foxing and tanning to pastedowns and endpapers. Pen inscriptions to front endpaper and heavier ink marks and tanning to text block edges. Both hinges are cracked with exposed netting and cracks to guttering with exposed netting. Binding is loose. Boards have visible rubbing and noticeable corner bending. Fair crushing to spine ends and minor rubbing to spine.