Head of state 1911 by her grandson, King George V; or the monument, placed in front of the Victoria Memorial Hall, Kolkata (Calcutta) (1921), commemorating Queen Victoria's reign as Empress of India from 1876. Another, twentieth century, example is the Mount Rushmore National Memorial, a group sculpture constructed (1927–1941) on a conspicuous skyline in the Black Hills of South Dakota (40th state of the Union, 1889), in the midwestern United States, representing the territorial expansion of the United States in the first 130 years from its founding, which is promoted as the "Shrine of Democracy". Former Presidents of the United States, while holding
Mount Rushmore of Mount Rushmore", posing for photographs with thousands of tourists. He became one of the most photographed people in the world. The ongoing conservation of the site is overseen by the National Park Service. Physical efforts to conserve the monument have included replacement of the sealant applied originally by Gutzon Borglum, which had proved ineffective at providing water resistance. The components of Borglum's sealant included linseed oil, granite dust, and white lead, but a modern silicone replacement is now used, disguised with granite dust. In 1998, electronic monitoring devices were installed to track movement in the topology of the sculpture