Cy Young tops list of sharpshooters
So the next step is to look for pitchers who walked very few batters. Simple enough except if you make a list of the six pitchers who walked the fewest batters per nine innings, you wind up with six pitchers who worked in the 19th century. Remove the 19th century from your search, and you wind up with six pitchers who worked in the first decade of the 20th century. We could begin with 1910 but that's not only arbitrary, it's certainly unfair to Cy Young and his contemporaries.