1955. 23rd Edition. 1501 pages. Blue jacket over blue cloth. Pages are in good condition with a firm binding. Endpapers and page edges are lightly tanned and foxed. Boards are a little rub worn, slight shelf wear to corners, spine and edges. Corners are a little bumped. Spine ends are mildly crushed. Tanning to spine and edges. Light wear to unclipped dust jacket with tears, nicks and creases to spine, edge and corners. Tanning to spine and edges. Water marks to edges and corners.