Highly technical book built out of material written over a period of years by the man who was probably the world's greatest authorities on horology. This book is heavily weighted on the side of watches rather than clocks. The emphasis is definitely scientific, dealing with ""escapements"" (part of the mechanism, to you-and me), rather than with cases, styles, fashions, etc. The history of the development of watch movements comes through the learned discussion of specific finds in the author's long record of collecting. Brief sections devoted to clock movements-again virtually nothing on periods and styles and types. The last part of the book deals with the famous horologists. Illustrated with photographs and with numerous scientific drawings and diagrams. A book of interest not to antiquarians in general, but to collectors of time places, to watch makers and clock makers today who have an interest in the background of their craft.