1947. Fourth edition. 371 pages. No dust jacket. Green cloth covered boards with gilt. Black and white photographs and diagrams. Pages remain bright and clean with minimal tanning and foxing. Binding remains firm. A previous owner's name to front free endpaper. Boards have moderate shelf wear with mild bumping and fraying to corners and crushing and fraying to spine ends. Some mild marks and staining to surfaces. Gilt lettering to spine is slightly dulled. Book has slight forward lean.