February 9, 1927 

 Fall 1927 

 January 10, 1928 

 1929 



October 29, 1929 

 June 19, 1930 

 1930 



April 1931 

 June 30, 1934 

 1940 



December 7, 1941 

 June 30, 1944 

 January 12, 1945 

 October 23, 1946 

 July 31, 1947 



May 26, 1948 



1949 (?) 



December 1952 

 January 2, 1953 

 Fall 1955 

 July 1, 1957 



February 4, 1958 

 August 1958 



May 13, 1960 



January 1962 



1960 

 1963 



July 1. 1963 



October 15, 1963 



January 31, 1964 

 February 1, 1964 

 February 1, 1965 



July 1, 1965 

 July 1, 1965 



Summer 1965 

 September 16-19, 1965 

 March 1966 



March 24, 1969 



Secretary Walcott dies. 

 Rotunda closed. 



Charles Greeley Abbot appointed fifth Secretary. 



Decking put in east range, ground floor. 



Rotunda reopened. 



Wings authorized by Congress. 



War Collection moved to Arts and Industries. 



Decking of west range and west north range begins. 



Heating and electrical plants cease operations. 



Conversion to alternating current begins. 



America enters World War II. 



Secretary Abbot retires. 



Alexander Wetmore appointed sixth Secretary. 

 100th anniversary of Smithsonian Institution noted. 

 Department of Biology divided into departments of 

 Botany and Zoology. 



A. Remington Kellogg appointed Director, U.S. National 

 Museum. 



Ice plant ceases operation. 

 Secretary Wetmore retires. 



Leonard Carmichael appointed seventh Secretary. 



Junior League begins docent tours in Museum. 



LI.S. National Museum divided into Museum of History 



and Technology and Museum of Natural History. 



A. Remington Kellogg appointed Assistant Secretary. 



A. C. Smith appointed Director, Museimi of Natural 



History. 



Funds for east wing construction appropriated by 

 Congress. 



T. Dale Stewart appointed Director, Museiun of Natural 

 History. 



Construction begins on east wing. 



Construction begins on west wing. 



Department of Entomology formed from Division of 



Entomology. 



Department of Geology divided into departments of 



Paleobiology and Mineral Sciences. 



Secretary Carmichael retires. 



S. Dillon Ripley appointed eighth Secretary. 



Bureau of American Ethnology and Department of 



Anthropology merge to form Smithsonian Office of 



Anthropology. 



Smithsonian Office of Ecology formed. 



Department of Zoology divided into departments of 



Invertebrate and Vertebrate Zoology. 



Department of Botany moved to Museum from Castle. 



200th anniversary of birth of James Smithson celebrated. 



Richard S. Cowan appointed Director, Museum of 



Natural History. 



Official name becomes National Museum of Natural 

 History. 



