In 1936, Bovet created and patented a “mono-rattrapante” chronograph system that acted similarly to a split-seconds mechanism, however without the heavy cost to manufacture. The mechanism was operated through the top chronograph button, while the lower button would stop it and when released allowed the time to catch up to the actual time. This was done via tension in a hairspring that built up as the chronograph button was held, and when released the hairspring unwound.

The present example is one of the best to be offered at auction. Not only is the case unpolished, but the dial has aged to a lovely brown over the years, adding charisma to an already beautiful watch. Crisp and clean, with part of the case number stamped to the underside of the lug “779”, this watch is an excellent example of early 20th century innovation.