presidency and vice-presidency were vacant simultaneously, then the speaker would become acting president, after resigning from the House and as speaker. Ratification of the Twenty-fifth Amendment in 1967, with its mechanism for filling an intra-term vice-presidential vacancy, has made calling on the speaker, president pro tempore, or a cabinet member to serve as acting president unlikely to happen, except in the aftermath of a catastrophic event. However, only a few years after it went into effect, in 1973, at the height of Watergate, Vice President Spiro Agnew resigned. With Agnew's unexpected departure and the state of Richard Nixon's presidency, Speaker Carl Albert was suddenly first in line to become acting president. The vacancy continued until Gerald Ford was sworn in as vice president. Albert was also next in line from the time Ford assumed the presidency following Nixon's resignation from office in 1974, until Ford's choice to succeed him as vice president, Nelson Rockefeller, was confirmed by Congress. See also Party leaders of the United States House of Representatives Party leaders of the United States Senate References Bibliography Garraty, John, ed. American National Biography (1999) 20 volumes; contains scholarly biographies of all speakers no longer alive. Green, Matthew N. The Speaker of the House: A Study of Leadership (Yale University Press; 2010) 292 pages; Examines partisan pressures and other factors that shaped the leadership of the speaker of the U.S. House of Representatives; focuses on the period since 1940. Grossman, Mark. Speakers of the House of Representatives (Amenia, NY: Grey House Publishing, 2009). The comprehensive work on the subject, covering, in depth, the lives of the speakers from Frederick Muhlenberg to Nancy Pelosi. Remini, Robert V. The House: the History of the House of Representatives (Smithsonian Books, 2006). The standard scholarly history. Rohde, David W. Parties and Leaders in the Postreform House (1991). Smock, Raymond W., and Susan W. Hammond, eds. Masters of the House: Congressional Leadership Over Two Centuries (1998). Short biographies of key leaders. Zelizer. Julian E. ed. The American Congress: The Building of Democracy (2004). A comprehensive history by 40 scholars. External links "Capitol Questions." C-SPAN (2003). Notable elections and role. The Cannon Centenary Conference: The Changing Nature of the Speakership. (2003). House Document 108–204. History, nature and role of the speakership. Congressional Quarterly's Guide to Congress, 5th ed. (2000). Washington, D.C.: Congressional Quarterly Press. Wilson, Woodrow. (1885). Congressional Government. New York: Houghton Mifflin. Speaker of the