Bill Klem, behind the plate at the Reds game in Cincinnati, celebrates his 35th anniversary as a National League umpire. He then calls the 10 – 5 Reds loss to Brooklyn.

On May 10, 1939 — Bill Klem, behind the plate at the Reds game in Cincinnati, celebrates his 35th anniversary as a National League umpire. He then calls the 10 – 5 Reds loss to Brooklyn.

Source:
Baseball Reference May 10