Charles Rosat
Charles Rosat-Bôle (1874-1930) was a clock maker and adjuster responsible for many of the prized Zénith won in chronometry in the pre-World War II period.
Charles Rosat was born in 1874. He married Rose-Lucy "Lucy" Bôle (daughter of gold watch case maker Louis Bôle-Baillot and Héléne Baillot) and was known formally after this as Charles Rosat-Bôle. The couple had 4 surviving children: Charles Rosat-Regez, Marie-Louise Rosat, William Rosat, and Jeanne-Denyse Rosat; another daughter, Lucy, died at 20 in 1923.
Rosat had a public feud with professor Louis-Camille Calame-Stattmann over his so-called "collar cock with mobile disc". Rosat claimed to have invented this fine adjuster mechanism but Calame-Stattmann disputed this and the pair feuded in the press in 1904.
Rosat was hired by Georges Favre-Jacot to bring his skills to Zénith in 1907. He became part of the Cantonal Commission of the Neuchâtel Observatory in 1908 and the Le Locle municipal authority and school board from 1915 to 1923.
Charles Rosat became a director of Zénith in 1918 under Jämes Favre and joined him in managing the subsidiary Compagnie Zénith of France in 1922. That same year Favre brought Rosat in to newly-acquired Le Phare as part of his management team along with Albert Piguet and Jämes Perrenoud. After the ouster of Jämes Favre, Rosat remained a director of Zénith under Ernest Strahm until his death in 1930.
Rosat moved his operation under his own name to Boudry in 1913 but this name was removed in 1919 and became known as a branch of Zénith by 1923. He remained there to work and to study the use of elinvar in balances in his later years. Rough clock components were produced in Le Locle and shipped to Boudry for finishing in Rosat's workshop.
Charles Rosat died in Boudry on August 17, 1930 after a short illness. His obituaries conflict regarding his age, with one claiming 50 years old but most saying 56.