I recently acquired an old Colt revolver in relic condition (rough). In disassembly I found a small scrap of paper with initials and an address. This revolver was made between 1898 -1902. Due to 1 digit in the serial # being worn to the point that it's illegible that's as close as I can date it. The paper is white with blue lines, looks to me as being more modern than the revolver. It's from a small little notebook like one might carry in his pocket for addresses & such. It does have a zip code. Anyone know when ruled notebooks like this became common? When did zip codes start being used? I did a Google earth search of the address and it showed a farm or ranch in rural MO. There is a different set of initials carved in the inside of the grips. Also a couple of notches carved in the grips. Ammunition for this old Colt (41 long Colt) has not been made since the 1930s except for 1 last run made by Winchester for a Texas hardware chain in the 60s. Just as an aside this is the caliber favored by Billy the kid. And the same model revolver carried by Teddy Roosevelt up some hill in the Spanish-American war.