1920. No Edition Remarks. 270 pages. No dust jacket. Brown cloth covered boards. Black and white diagrams throughout. Pages with some foxing and tanning, particularly to endpapers and textblock edges. Binding remains firm. Minor inscriptions to front endpapers. Examination paper from 1929 tucked inside. Boards have moderate shelf wear with bumping and fraying to corners and crushing and fraying to spine ends. All surfaces tanned and sunned, particularly spine. Some additional marks and staining to surfaces. Boards are slightly bowed.