submerging their feet in ice water, three doses of castor oil, and five enemas. Only one candidate, Jim Lovell, was eliminated on medical grounds at this stage, a diagnosis that was later found to be in error; thirteen others were recommended with reservations. Gilruth found himself unable to select only six from the remaining eighteen, and ultimately seven were chosen. Despite their rejection from the first group of astronauts, many of the 25 finalists who were passed over still had successful military careers. Three eventually became astronauts: Pete Conrad and Jim Lovell, who were selected with the next group in 1962; and Edward Givens, who was selected with the fifth group in 1966. Others achieved high rank: Lawrence Heyworth Jr. became a rear admiral, Robert B. Baldwin and William P. Lawrence became vice admirals, and Thomas B. Hayward became an admiral. He commanded the Seventh Fleet and the Pacific Fleet, and was Chief of Naval Operations. Three of the finalists later died in aircraft accidents: Halvor M. Ekeren, Jr., on April 8, 1959, Jack B. Mayo on January 11, 1961, and Hal R. Crandall on July 24, 1963. Finalist Robert G. Bell died in the May 16, 1965 explosion of multiple aircraft at Bien Hoa Air Base, Vietnam. Eligibility The seven original American astronauts were Navy Lieutenant Scott Carpenter, Air Force Captain Gordon Cooper, Marine Lieutenant Colonel John Glenn, Air Force Captain Gus Grissom, Navy Lieutenant Commander Wally Schirra, Navy Lieutenant Commander Alan Shepard, and Air Force Captain Deke Slayton. All were male and white. Women were not yet accepted into the military test pilot schools, and the first African American to graduate from the USAF Experimental Test Pilot School, John L. Whitehead Jr., did so only in January 1958, and was not one of the finalists. Yet the Mercury Seven were similar beyond what was a simple result of the selection criteria. Four were their fathers' namesakes. All were the eldest or only sons in their families. All were born in the United States, and were raised in small towns. All were married with children, and all were Protestants. Their ages at the time of selection ranged from 32 (Cooper) to 37 (Glenn). Shepard was the tallest, at the maximum height of ; Grissom, the shortest at . Weight was not a firm criterion like height, as losing weight was always possible, but the Mercury spacecraft set a limit