Important Collectors Wristwatches, P...
Geneva, Hotel Des Bergues, Oct 20, 1991
Chas. Haley,Invenit et fecit, London, No. CN11592.
Full plate movement with fusee, Peto crossdetent escapement, three armed compensated balance.circa 1790. Without dial. Chamb. p. 239. O. T.L. No.28, illustration No.6. This escapement was devised in order to circumvent the patent taken out by Earnshaw.