Raimey,
I'm not sure about the dates, but this gun has a May 27 1902 patent date stamped on it. When I compared it to the patent record, it turned up patent # US701158...I checked it to see if Davenport was still in Norwich in 1902 and he was...

http://patimg2.uspto.gov/.piw?docid=US00...26RS=PN/0701158

I hope this link works...

I have about 10-15 Davenport patents...some are obviously for doubles...some are for single shots...or so I thought, until today...three of the four patent dates on this double were issued for and drawn on single shots...565606 and D33075 are the other two...there is however another patent date Dec 15 '91...but I don't have a match in my files for that date...maybe I'm reading it wrong...I'll post another pic so you can decide for yourself...

I would love to contribute to a thread about this last frontier, unfortunately I have only a few (4)catalogs, but a mountain of patents.

Bob Chambers