1960. 4th edition. 232 pages. Blue dust jacket over blue cloth. Contains black and white diagrams. Previous owner's inscription to front pastedown. Pages remain bright and diagrams clear throughout with occasional thumb marking present. Boards have mild shelf wear with light rubbing and corner bumping. Some light marking and crushing at spine ends. Unclipped jacket has light edge wear with minor tears and chipping. Mild rubbing and water marking with tanning to spine.