1957. Reprinted. 48 pages. Pictorial dust jacket over pictorial cloth. Black and white diagrams throughout. Colour frontispiece. Pages remain bright and clean with minimal tanning and foxing. Binding remains firm. Boards have light shelf wear with minor corner bumping and crushing to spine ends. Some mild marks and staining to surfaces. Clipped jacket has light edge wear with minor tears, chipping and creasing. Some rubbing and marking to surfaces.