Instead of writing an account of his career I will instead direct you to writeup by Tom Simon at the SABR Biography Project. It is excellent. Below is an excerpt:
"My first day on the field with Wilmington, I kicked on a decision and [teammate] Bill Everson, the old pitcher, called me 'Rowdy John,'" Hummel recalled. "The newspapers took it up and I made up my mind right then that I'd never kick again. When the papers and the players saw I was quiet, Everson called me 'Honest John' and then finally 'Silent John,' which has stuck to me ever since." The "Honest John" appellation, according to the Brooklyn Eagle, came because Hummel "was always striving to win, even when the lead of the opposing team was great enough to bury the hopes of the ordinary player." John had yet another nickname, "Colonel Pinch," which he thought came "maybe from the fact that I was lucky enough to come up with a hit in the pinches," but "Silent John" was by far the most popular of his various nicknames.Here is another great excerpt:
In his later years he disdained the livelier ball. "In the good old days we played heart and soul for one run, whereas now they play for 10 or 12," he said.