1958. 21st Edition. 300 pages. No dust jacket. Blue cloth with gilt. Pages remain clear with minimal tanning and foxing. End papers are more notably foxed. Binding remains firm. Boards have mild edge-wear with slight rubbing to surfaces. Mild crushing to spine ends. Gilt lettering has become dull. Sunning to spine. Book has a slight forward lean. Cloth has minor damp and dust stains.