The president pro tempore of the United States Senate ( or ), also president pro tem, is the second-highest-ranking official of the United States Senate.
 of the United States Constitution provides that the Vice President of the United States is, despite not being a senator, the President of the Senate, and mandates that the Senate must choose a president "pro tempore" to act in the Vice President's absence.
 Unlike the vice president, the president pro tempore is an elected member of the Senate, able to speak or vote on any issue.
 Selected by the Senate at large, the president pro tempore has enjoyed many privileges and some limited powers.
 During the vice president's absence, the president pro tempore is empowered to preside over Senate sessions.
 In practice, neither the vice president nor the president pro tempore usually presides; instead, the duty of presiding officer is rotated among junior senators of the majority party to give them experience in parliamentary procedure.
The presidency of Gerald Ford began on August 9, 1974, when Gerald Ford became President of the United States, and ended on January 20, 1977, a span of days.
 Ford, the 38th United States president, succeeded Richard Nixon, who had resigned from office.
 Prior to this he was the 40th Vice President of the United States, serving from 1973 until President Richard Nixon's resignation in 1974.
 He was the first person appointed to the vice presidency under the terms of the Twenty-fifth Amendment to the United States Constitution, following the resignation of Vice President Spiro Agnew on October 10, 1973.
 Ford has the distinction of being the first, and to date the only person to have served as both vice president and president without being elected to either office.
Andrew Jackson (March 15, 1767 – June 8, 1845) was an American soldier and statesman who served as the seventh President of the United States from 1829 to 1837.
 Before being elected to the presidency, Jackson gained fame as a general in the United States Army and served in both houses of Congress.
 As president, Jackson sought to advance the rights of the "common man" against a "corrupt aristocracy" and to preserve the Union.
In 1973, Republican Vice President Spiro Agnew was forced to resign following a controversy over his personal taxes.
 Under the terms of the 25th Amendment, a vice presidential vacancy is filled when the president nominates a candidate who is confirmed by both houses of Congress.
 Republican President Richard Nixon thus had the task of selecting a vice president who could receive the majority support of both houses of Congress.
 Nixon considered selecting former Texas Governor John Connally, New York Governor Nelson Rockefeller, and California Governor Ronald Reagan.
 However, Nixon settled on House Minority Leader Gerald Ford of Michigan, who was popular among the members of Congress and who was good friends with Nixon.
 Ford won the approval of both houses by huge margins, and was sworn in as the 40th Vice President of the United States on December 6, 1973.
 In 1974, Ford ascended to the presidency after the Watergate scandal led to the resignation of President Nixon.
John Henry Summerskill (March 26, 1925 – June 14, 1990) was a Canadian educator who served as the seventh president of San Francisco State University in the 1960s.
 Prior to this he was Vice President for Student Affairs at Cornell University.
 In the 1970s he was named President of Athens College in Greece.
 He later moved to New Jersey where he established a vineyard and became president of the New Jersey Wine Growers Association.
Calhoun County is a county in the U.S. state of Michigan.
 As of the 2010 census, the population was 136,146.
 The county seat is Marshall.
 The county was established on October 19, 1829 and named after John C. Calhoun, who was at the time Vice President under Andrew Jackson, making it one of Michigan's Cabinet counties.
 County government was first organized March 6, 1833.
The first inauguration of Andrew Jackson as the seventh President of the United States was held on Wednesday, March 4, 1829 at the United States Capitol in Washington, D.C..
 The inauguration marked the commencement of the first four-year term of Andrew Jackson as President and the second term of John C. Calhoun as Vice President.
 Chief Justice John Marshall administered the presidential oath of office.
 Calhoun resigned into this term, and the office remained vacant for the balance of it.
 (Prior to ratification of the Twenty-fifth Amendment in 1967, no constitutional provision existed for filling an intra-term vacancy in the vice presidency.)
The election of President and Vice President of the United States is an indirect election in which citizens of the United States who are registered to vote in one of the 50 U.S. states or Washington, D.C. cast ballots for members of the U.S. Electoral College, known as electors.
 These electors then in turn cast direct votes, known as electoral votes, for President and Vice President.
 The candidate who receives an absolute majority of electoral votes for President or Vice President (currently, at least 270 out of a total of 538) is then elected to that office.
 If no candidate receives an absolute majority for President, the House of Representatives chooses the President; if no one receives a majority for Vice President, then the Senate chooses the Vice President.
Frank Harmon currently serves as executive vice president and chief operating officer for APP Pharmaceuticals.
 Prior to the spin-off of the proprietary business, Mr Harmon served as executive vice president and chief operating officer of Abraxis Pharmaceutical Products (APP) since September 2006, after having joined Abraxis in May 2006 as the executive vice president of global operations.
 Mr. Harmon oversees global manufacturing operations as well as the corporate quality assurance and quality control and the supply chain organizations as well as Generic Product Development, Regulatory Affairs and Operational Excellence.
 Prior to joining Abraxis, Mr. Harmon was the senior vice president, manufacturing operations for the Sterile Technologies Group at Cardinal Health where he was responsible for multiple sites throughout the United States and Puerto Rico.
 Mr. Harmon has also served as vice president, biopharmaceutical operations for Aventis Behring.
The Office of the Vice President includes personnel who directly support or advise the Vice President of the United States.
 The Office is headed by the Chief of Staff to the Vice President of the United States, currently Nick Ayers.
 The Office also provides staffing and support to the Second Lady of the United States.
 It is primarily housed in the Eisenhower Executive Office Building, with offices for the Vice President also in the West Wing, the U.S. Capitol and in the Vice President's official residence.

Question: What Michigan county is named after the Vice President of the seventh President of the United States?
Answer: Calhoun County