1967. Revised edition. 821 pages. Pictorial dust jacket over pictorial cloth covered boards. Black and white diagrams throughout. Pages and binding are presentable with no major defects. Minor issues present such as mild cracking, inscriptions, inserts, light foxing, tanning and thumb marking. Overall a good condition item. Boards have mild shelf wear with light rubbing and corner bumping. Some moderate marking and tanning. Unclipped jacket has heavy edge wear with tears, chipping and creasing. Some tanning and foxing to all surfaces, particularly to spine. A small label on front.