These antique geometry books are great for collectors or those interested in historical educational materials. To use them, simply open the pages and start reading. When handling, make sure your hands are clean to avoid further soiling. Since the spine of 'Plane and Solid Geometry' is pulling from the binding, be gentle when opening and closing it. To maintain these books, store them in a dry and cool place, away from direct sunlight. You can also use a bookend to support them and prevent the bindings from getting damaged further.