1970. Ninth Revised Edition. 152 pages. No dust jacket. Blue cloth covered boards with gilt. Pages remain clear with minimal tanning and foxing. End papers are more notably foxed. Binding remains firm. Boards have moderate edge-wear with bumping to corners and rubbing to surfaces. Mild crushing to spine ends. Boards have minor damp and dust stains. Book has a slight forward lean. Gilt lettering is darkened.