1969. First Edition. 146 pages. Paperback book with pictorial cover. Contains black and white diagrams. Clean pages and diagrams with light tanning and mild foxing throughout. Ink stamp inscription to half title page. Binding remains firm. Paper covers have moderate edge-wear with slight rubbing to surfaces and curling to corners. Lettering is bright and clear. Moderate tanning to spine and covers. Visible wear marks to covers.