Explanatory notes
… and hairspring or by any other regulating system capable of determining intervals of time, and exceeding 12 mm in … motor or the electro‑magnet, a clock train, i.e., a train containing parts such as the first, second, third and fourth … shaft. These clock movements may be unpolished, polished, nickel‑plated, rhodium‑plated, silvered, gilded, varnished, …