Nice pickup! I was going to bid on that one, but missed out. I have some older Davis bottles, but that mold seam is pretty wild. Definitely 1860s, maybe early 1870s.
normally they do have either a strait vertical or round key mold. The size and shape of that one is a little different too... If you ever want to let go of it let me know, I'd like to have it if it can be attributed to New London, which had some odd mold cuts in a few bottles...