1956. Twenty-Third Impression. 491 pages. Dust jacket over red cloth. Book is in better condition than most examples of this age. Neat, clean, well bound pages with very minimal foxing, tanning and thumbing. Small inscriptions and neat labels may be present. Boards have mild shelf wear with light rubbing and corner bumping. Some light marking and sunning. Unclipped jacket has light edge-wear with minor tears and chipping. Mild rubbing and marking.