1951. Reprinted. 117 pages. Pictorial dust jacket over pictorial cloth covered boards. Black and white photographs and diagrams. Pages with some foxing and tanning, particularly to endpapers and textblock edges. Binding remains firm. Boards have mild shelf wear with light rubbing and corner bumping. Some moderate marking and tanning. Unclipped jacket has light edge wear with minor tears, chipping and creasing. Some tanning and foxing to all surfaces, particularly to spine.