Please note that the content of this book primarily consists of articles available from Wikipedia or other free sources online. William H. "Dad" Clarke (January 7, 1865 in Oswego, New York - June 3, 1911 in Lorain, Ohio), was a professional baseball player who played pitcher in the Major Leagues from 1888-1898. He would play for the Chicago White Stockings, New York Giants, Louisville Colonels, and Columbus Solons. Major League Baseball (MLB) is the highest level of professional baseball in the United States and Canada, consisting of teams that play in the National League and the American League. The two leagues merged in 2000 into a single MLB organization led by the Commissioner of Baseball after 100 years as separate legal entities.