In 1950 Penn State hired Milton Eisenhower, who was the President of Kansas State University, to be its President, and he served for six years. In 1953, the school's name changed to The Pennsylvania State University. Eisenhower's older brother Dwight Eisenhower delivered the Commencement address in June 1955. In 1955, Penn State dedicated its nuclear reactor, the second in the nation to be operated on a college campus. Under Eisenhower's successor, Dr. Eric A. Walker, the university developed rapidly. Under his leadership, which lasted from 1956–1970, the university added hundreds of acres of surrounding land, and nearly tripled enrollment to 40,000.