Today marks the 100-year anniversary of the passage of The Apportionment Act of 1911 (AKA Public Law 62-5), which established 435 as the fixed number of members in the U.S. House of Representatives.

Related Fact: The longest serving member in the history of the House is current Representative John D. Dingell of Michigan, who has been in office since December 13, 1955. He was preceded in office by his father, who had served since 1933.

[Sources:Office of the Clerk and Dingell.House.Gov. See previous Numbers of the Day here. ]