1946. Fourth Edition. 148 pages. No dust jacket. Beige Pictorial paper covered boards, with green cloth to spine. Contains black and white photographs and diagrams throughout. Pages are lightly tanned, but text remains clear. Binding is firm. Previous owner's inscription to front pastedown. Boards have moderate shelf-wear, with noticeable corner bumping and some scuffing to edges. Spine is noticeably creased. Visible ink mark to front board. Boards are noticeably bowed.