There is established in the Smithsonian Institution a bureau which shall be known as the National Portrait Gallery. The functions of such bureau shall be those authorized by this subchapter. The use for the purposes of the Gallery of any part of the building transferred to the Smithsonian Institution pursuant to the Act of March 28, 1958 (72 Stat. 68), is authorized.
The Gallery shall function as a free public museum for the exhibition and study of portraiture and statuary depicting men and women who have made significant contributions to the history, development, and culture of the people of the United States and of the artists who created such portraiture and statuary.