Posted By:
fkwOn mine......
The Jackson (bottom right) is blank.
The Waner has a single horizontal line 3/4" from the bottom.
The Judge has "POST CA"
The Kamm has "RD" & stampbox.
And if the other 2 known cards have postcard backs facing the same direction...
The Cochrane and Critz would be blank.
The Grove and Vance would have the line.
The Gehrig and O'Doul would have the "POST CA"
The Donahue and Shire would have the "RD" & Stampbox
Adams page has pictures of the other 2 known cards
http://imageevent.com/exhibitman/interestingexhibitcards