David-Henri Elffroth

David-Henri Elffroth, Geneva, circa 1875. Extremely rare and probably unique, 18 ct. gold miniature double-train key-wound doctor's pendant watch with independent dead seconds, honoured by a prize from the Geneva Société des Arts. Two-body, in shape of a small oval pillbox, polished, loop pendant, loose ring, concave back made to fit the curvature of the finger. 13x17.6 mm, weight 5 grams (including dial and hands), oval, nickel, built on two levels, 16 jewels, cylinder escapement, gold three-arm balance, blued-steel flat balance spring, independent dead seconds by a flirt acting on the escape wheel pinion, regulator through the dial, dead seconds activated by a small slide on the band of the case.Dim. 16 x 19 mm. Published in the Sandberg book, pages 188-189. Notes This is the smallest independent dead seconds watch ever made; in 1877 the Société des Arts honoured the maker with their annual prize for design and execution, a very prestigious event at the time in the world of horology. Apparently, even Geneva's famous watchmakers considered it quite a feat to make such a small double-train watch. The watch was probably designed to be worn either as a ring or a pendant, the original engraving shows it mounted on a ring.David-Henri Elffroth'établisseur', made repeating watches, independant dead seconds watches, and chronometers. He specialised in very small watches.