Oldest card of George Halas I've ever seen! This 1915 RPPC shows Potsy Clark and George Halas while at Illinois.
They both broke their jaws that season and the press called them the "Order of the Broken Jaw". Note the head harnesses they are wearing. How would you like to play football with that on?
Numerous articles were written about it and some showed a cropped version of this image.
jeff