During the last quarter of the 18th century, several watchmakers tried to produce watches with dead center-seconds hands, much in favor among the scientific community and on the Chinese market. The first attempt, made by Moïse Pouzait around 1786, featured a lever escapement associated with a large seconds-beating balance. It was much appreciated by the Chinese before Jacot's invention, circa 1840, of the so-called "Chinese duplex" escapement with double-tooth arrangement. The Jacot escapement, like any duplex escapement, is a frictional one the friction from the escape wheel is constantly present.The escapement in the present watch is frictionless the balance, when not receiving an impulse, rotates freely. This is achieved by a clever use of Robin's double-locking lever with two sharp pallets which lock and unlock the double teeth. The full cycle requires four swings of the balance: 1. The entry pallet unlocks and the escape wheel delivers an impulse. The balance receives enough momentum to swing about 270o. The exit pallet locks the first half of a tooth. 2. The exit pallet unlocks and the entry pallet locks the first half of the next tooth. 3. The entry pallet unlocks and exit pallet locks thesecond half of its tooth. 4. The exit pallet unlocks and the entry pallet locks the second half of its tooth. From this it is clear that the energy stored in the balance has to provide for four reversals of swing and four unlockings. It is a very clever arrangement, and although complicated, works perfectly. According to the Deutsche Urmacher-Zeitung, quoted in the December 1904 issue of the Journal Suisse d'horlogerie, the escapement was invented by Mr. J. Kukowitz from Bruxelles. The drawing of a movement with Kukowitz's escapement printed in the Journal leaves little doubt that the escapement in the present watch was made by the same maker.The split mechanism. Until the invention of the so called “heart piece” by Henri-Féréol Nicole, an employee of Nicole & Capt, which was first shown at the 1862 London Exhibition, split-seconds watches were based on the principle of two wheels held together by a long coiled elastic spring, an arrangement invented by Joseph Thaddeux Winnerl about 1830. Quite rare, they are sometimes found in Arnold, Dent, and Frodsham watches. The present watch takes this idea to the extreme, for it has two such mechanisms working independently, both directly from the going train. The first one splits the central dead seconds, the other the minutes and the hours shown on the dial marked “DEPART”. The latter mechanism, which shows the difference between two events, appears to be unique; no other similar one is known to exist. J. Barth et Fils. The Davoine directory states that in 1875-76 they were at Parc 15 in La Chaux-de-Fonds and were listed as “Fabricants et négociants en horlogerie”.