There was a pretty hilarious thread about this card in February of last year:
https://www.net54baseball.com/showthread.php?t=314960
My favorite comment:
Originally Posted by Smarti5051
"
Plot twist: Joe Jackson could not read or write. Maybe he saw a bunch of Babe Ruth autographed pictures and practiced trying to mimic the signature. So, when he is requested for an autograph, he just signs "Babe Ruth" thinking that is his own signature. It could explain why it is almost impossible to find a "Joe Jackson" autograph and why there are so many "Babe Ruth" autos out there."