1920. 6th Edition. 517 pages. No dust jacket. Green cloth. Black and white diagrams and maps within. Pages are lightly tanned and thumbed at the edges, with light foxing. Binding has remained firm. Boards are a little rub worn, slight shelf wear to corners, spine and edges. Corners are a little bumped. Spine ends are mildly crushed. Light tanning to spine and edges. Boards are bowed. Book has a forward lean.