This is a most comprehensive Guide to the world of Clocks, covering 3 centuries. Extensive history, illustrations & pictures, lists of important facts, as well as so many internet resources for pricing or buying any type of clock, are included. As a Certified Appraiser, I have spent many hours digging for the information that is all right here in one place. The format is easy to follow, the text is clear and precise; the amount of information seems endless; the many internet locations provide more paths to anything you would want to know. An excellent tool, well worth the price. 5 Stars!