1970. S I Metric Edition. 299 pages. Illustrated dust jacket over red cloth covered boards with gilt. Pages remain clear with minimal tanning and foxing. Previous owner's inscription to front free end-paper. Binding remains firm. Boards have mild edge-wear with slight rubbing to surfaces. Mild crushing to spine ends. Gilt lettering is bright and clear. Book has a slight forward lean. Unclipped jacket has light edge-wear with tears and creasing.