Previously in the Clutton collection, this movement is described and illustrated in his book: Collector's collection. Reputed to be the first movement with a lever escapement ever made in France and the second in the world after that made by Mudge, it has been studied in several publications. The first one by Robert H. A. Miles, published by the Antiquarian Horological society in Pioneers of precision tnnekeeping, gives a complete description of the wheel train and an exhaustive analysis of the action of the escapement; however the watch is attributed to Julien Le Roy and therefore supposed to be made before his death in 1759. This mistake was corrected by Cecil Clutton in his book, following the stuc-lies made by Charles Allix and Giuseppe Brusa and the new evidences given in their articles published in Antiquarian Horology. It has been described more recently by Norbert Eder in his article on Pierre Le Roy, published in Llhren, No. 1 - 1986, Callwey Editions, and by A. Chapiro in Histoire de l'échappement à ancre sur le continent européen (A.N.C.A.H.A. Bulletin No. 45).