1956. 6th Edition, Revised. 474 pages. No dust jacket. This is an ex-Library book. Blue cloth. Library copy, with expected inserts and inscriptions. Black and white illustrations throughout. Binding remains firm. Pages and illustrations have light tanning and foxing throughout. Water staining to some page edges, text remains unaffected. Paper worn away to pastedowns. Boards have moderate shelf-wear with bumping to corners and rubbing to surfaces. Light tanning to spine and edges with crushing to spine ends. Staining overall.