Posted By:
leonAt least one source says that, for dating of E120's, it's easily 1922. Vic Aldridge, pitched for the Cubs in 1917-18, and didn't pitch in the majors again until 1922. Gabby Hartnett was a rookie and there is a card of him (although not positive how you would tell that by one of "these" cards) but not one for Dazzy Vance. Go figure......
E121- estimated at 1921 and 1922.....There are many player/team scenarios here and not one makes either date definitive
E122- same as e121
E220- dated between 1921-1923....Distribution was possible in all of those years with the players that have been found to date.
Hal- go by what the big book SCD says....it looks to be as correct as is known.....(they've even got E135's correct, for Pete's sake) 
take care
leon