Likely taken in 1912 but no certainty since the Cubs wore the dark uniforms in 1911 and 1912.
1912 Heinie Zimmerman, Chicago Cubs Triple Crown Winner, Vintage 1 Action Photo
Chicago Cubs vintage photo print Wrigley Field photograph vintage
Heinie Zimmerman, Chicago Cubs, 1912 Stock Photo - Alamy
Chicago Cubs 1910's - TAILGATING JERSEYS - CUSTOM JERSEYS -WE HELP
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Zaid Walker - Baseball - Georgetown University Athletics
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Chicago Cubs 1911-1912 Throwback Wireless Magnetic Car Charger
Uni Watch - The best throwback uniform for each MLB team - ESPN