The cannon pinion started slipping after a few days. It's tricky to tight one of this type. It's fragile for one thing, but also if it is too tight that inner ring engaged during setting will slip. There is a very narrow range of "snug-ness" that will work.
Elgin serial number 3793826 is a grade 70, 18 size, 15 jewels, made about 1890. This is a B.W. Raymond model.
