Only looks like a Parker Bros. on the outside --
The patent for the lock mechanism used in the Philadelphia Arms Co. FOX gun was Patent No. 767,557 granted to Harry H. (Hunter) Fox, Ansley's younger brother. My guess is that Ansley may have had his brother file it because he still had some contractural ties to Winchester Repeating Arms Co. which he'd become a professional shooter for in early 1900. Patent No. 714,688 for a bolting mechanism, which Ansley applied for on January 17, 1902, when he was still actively shooting for Winchester was not used in the guns as made. I wonder if Winchester laid claim to it?
Ed,
Want to tell me the serial number of the gun so I can add it to my list?
Dave