He was an avid inventor and has a number of inventions to his credit. One of them is the first cotton candy (originally named Fairy Floss) machine, which he constructed in cooperation with John C. Wharton. This electric machine that melted sugar and then used forced air to push it through a wire screen was introduced at the 1904 St. Louis World's Fair. He was also a lawyer, author, and a leader of civic and political affairs.
William Morrison later became President of the Tennessee State Dental Association.