Waltham Crescent Street Model 1870: Square Impulse Jewel Pallet Fork
By 
Charles Vander Woerd’s innovative square impulse jewel was fitted on every Model 1870 Crescent Street produced at the Waltham factory. However, the novel shape introduces an efficiency issue within the escapement when paired with a standard pallet fork. To combat this challenge, Woerd devised a unique circular cutout in the pallet fork to receive the square jewel more effectively. This allowed the innovative escapement to operate efficiently and accurately enough for the demands of railroad service.
