1951. Fortieth Edition. 256 pages. No dust jacket. Blue cloth boards with lettering. Clean pages with light tanning and mild foxing throughout. More pronounced to free endpapers and pastedowns. Binding remains firm. Boards have mild edge-wear with slight rubbing to surfaces and bumping to corners. Lettering is bright and clear. Moderate sunning to spine and edges with crushing to spine ends. Book has a slight forward lean with bowed boards. Visible wear marks to boards.