In the 1930s, the facilities for animal research at the NIH campus at 25^th and E Streets, N.W., in Washington, DC, were becoming strained. The NIH and PHS leadership were thus receptive to the offer by Luke I. Wilson to donate his Bethesda estate to the federal government. When Dr. Thomas Parran became Surgeon General, he and his choice for NIH director, Dr. Lewis R. Thompson, decided to rebuild the entire NIH campus in Bethesda to allow room for expansion. The laboratories moved as their buildings were completed between 1938 and 1941. In October 1940, President Franklin Roosevelt dedicated the campus.