1937. First Edition. 99 pages. Grey jacket over grey cloth. Contains black and white diagrams throughout. Pages are mildly tanned, but text remains clear. Some noticeable foxing and marking to endpapers. Binding is firm. Previous owner's inscription to front free endpaper. Boards and spine have minimal shelf-wear, with mild corner bumping and crushing to ends. Spine is slightly sunned. Visible marks overall. Unclipped jacket. Noticeable tanning and foxing to all surfaces. Panels have light edgewear, with small tears, chips and creases, heavier to spine ends. Moderate marking to exterior.