1951. Third Annotated Edition. 541 pages. No dust jacket. Dark blue cloth with gilt lettering to spine. Pages remain bright with minimal tanning. Text is clear. Heavier tanning to endpapers & paste downs. Binding remains firm. Boards have moderate edge-wear with heavy bumping to corners and rubbing to surfaces. Visible tanning to spine and edges with crushing to spine ends. Gilt lettering is bright and clear to front board & spine.