Waltham Crescent Street Model 1870: Square Impulse Jewel

As evident in previous posts, Waltham’s Model 1870 Crescent Street is full of innovative advancements from the mind of Charles Vander Woerd. One such innovation is the square impulse jewel fitted on every Model 1870, a notable departure from the standard “D” shaped impulse jewels found in most American movements. For an unknown reason, this escapement design was not patented by Woerd until October 25, 1887, nearly two decades after his implementation in the Model 1870 Crescent Street.