Arthur Hamilton "Dad" Clarkson (August 31, 1866 – February 5, 1911) was an American pitcher in Major League Baseball from 1891 to 1896.

Clarkson was born in Cambridge, Massachusetts, and starred on the Harvard University baseball team in the 1880s.

The following season, Clarkson was outpitched by the other members of Baltimore's staff, and he played his final major league game on August 8.

He was fined by Cardinals owner Chris von der Ahe for making calls that went against the team.

In protest of the fine, Clarkson refused to make his scheduled August 1 start as a pitcher.