The full title is L' Horloge Astronomique de la Cathedrale de Bourges Son Histoire- Sa Rehabilitation by Alain Bougelot Jean Yves Catoire. ISBN 2-9526232-0-1 Printed in 2006. The book tells the history of the astronomical clock at the cathedral at Bourges This is very useful book to have if you are in the area (The Loire Valley in France), love old clocks and are going to see the Cathedral at Bourges. If you are fortunate enough to to in this situation this a must have book. Here is what the book looks like To my knowledge the only place to buy this book is at the tourist office on the square near the cathedral. the price is 15 euro. I saw the clock as part of a group tour. The guide know or at least said very little about it even in response to my questions. I am mostly a watch guy but I saw several things about the clock movement, which is on display in its own glass case. 1) It has a very odd pendulum which couples to the escapement via a jointed hinged arm 2) It has a kind of escapement I later learned is called a chevelle. This would make this an even amazing item than it is, since it was date 1454. This book tells the story in great detail. In outline 1) It was built as an astronomical clock under the order of the cannon in1454 and ran for several hundred years with daily winding operating with a foliot and verge escapement. It also struck bells. tehbook estimate the number of bel strikes and it is impressive! 2) The pendulum and new escapement were added in the 19th century (no real surprise except for how late) 3) The clock was retired and put in a museum 4) Like most Cathedrals it also has some very precise noon sun indicators 5) It s arguably the inspiration for the much more famous clock at Strasbourg. 6) It has a very accurate moon and sun, and therefore eclipse prediction system. Now it gets very interesting. During the 1990's it underwent a massive restoration done mostly by Aerospatial of Toulouse. They did all the modern aerospace analysis and CAD work to create a replica movement with some modern changes which they installed in a restored case. They treated and stabilized the original movement with all its additions and put it the case. Many of the drawings are reproduced in the book and most are labelled in English, but even if you don't read or speak French there is a lot you can get from this book. I have a very rudimentary French language ability but I read it cover to cover. It also helps to know a bit about French horological jargon but after a while I discovered the book itself has a very helpful glossary at the end. If you are going, try to get the book before you tour the cathedral. There is a lot I missed. The Cathedral is very comparable to Notre Dame in Paris but a lot less crowded. Bourges itself is very nice place to visit but the take away is that if you going, like clocks, and are going to the cathedral, you should consider hiking over the local tourist office and buying this book before your tour. Here are two of my shots of the clock As the photo shows there are explanatory plaques but our tour was too tightly scheduled to allow me to wander over and read or photograph them. A general group tour is not enough for a clock enthusiast. If this is your thing, allow a few hours for the clock. The cathedral itself is a real marvel and has quite a history but it is not a lot different from other French gothic cathedrals except that you can get better access to most of it. If you are going do only one or two this is good one but if you have been to Notre Dame, Chartre etc you have seen most of it before. For this cathedral, the clock is the thing and if you are like me, get the book.