Waltham Model 1870 Crescent Street (18-Size, 15 Jewels, Button-Set) [Regulator Patent Illustration]

Every Waltham Model 1870 Crescent Street movement features Charles Vander Woerd’s patent micrometric regulator, allowing precision changes in the oscillation rate of the balance wheel. Woerd received this patent December 27, 1870, almost a year after production began on the Model 1870. This was the first traditional micrometric regulator fitted on Waltham movements (Fogg’s vibrating hairspring will be covered in a future post) and represents a significant development in the American watchmaking industry. Elgin followed suit a few years later, implementing a regulator design by Moseley and Hunter.⠀
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Adapted iterations of the “star wheel” regulator design were used in production for several decades.