1961. Fourth Printing. 159 pages. Pictorial dust jacket over red cloth and black lettering. Contains black and white illustrations and diagrams. Binding remains firm. Illustrations are clear, with slight tanning. Front free end paper is missing. Pages remain bright with minimal tanning. Slight rusting to half-title page. Boards have light edge-wear with slight rubbing to surfaces. Mild crushing to spine ends causing cloth to fray. Unclipped jacket. Jacket has moderate edge-wear with chips, tears, and creasing. Noticeable sunning to spine and edges.