Whirling Psychrometer, 1950-1953
1950-1953
1950-1953
circa 1953
1953
1950
1953
1951
1951
1955; 1830
1950
1950-1951
1951
1951
1949
1950-1953
1950-1952
1949
1953
1953
1951
2000-100 BCE
circa 1950
1951-1953
1938 and 1951
1951-1953
May 1953
1950
1951
1950
circa 1950
1949
1949
1950
1953
circa 1950
circa 1950
1951
circa 1953
1950
1903 (original); 1982 (model)
1951
1951
1950
1950-1951
1949
1950
1951
1951
1951
circa 1953
1990-96