Jack Dempsey is considered by many as one of the greatest pound-for-pound boxers who ever fought in the ring.  He moved well and was extremely quick, agile, and skillful. A two-handed fighter whose jab was quick and accurate. Arguably one of the fight games great ring generals and trainers, he could punch as well as box in any space. Cool under pressure he could fight whatever style was needed to get the win. He often fought men 10-25 pounds heavier. In short, he was a crafty boxer-puncher and excellent ring general.

 

Jack Dempsey “the Nonpareil” along with Jack McAuliffe, “The Napoleon of the Ring” and John L Sullivan “Champion of Champions” were in the 1880’s and early 1890’s: The Three Champion Jacks of the World.

 

“Jack Dempsey, born John Edward Kelly, was an extremely popular fighter in America during the 1880’s and early 1890’s.  Jack began his athletic career as a collar-and-elbow wrestler, but soon he gave it up and switched to boxing exclusively. Most of his contests were fought with bare-knuckles or skin-tight gloves under London Prizefighting Ring rules.”

Source: http://www.cyberboxingzone.com/boxing/Article-Nonpareil.htm