
Oxygen cylinder used by climbers on 1953 Mount Everest expedition
1952-3
1952-3
1940
1830 (original); 1967 (model)
1939
1938
1940
1940
1938
1938
1938
1938
1940
1955; 1830
1938-1940
circa 1938
2000-100 BCE
1938
1938
1938 and 1951
1938
1938
1938
1939
1940
1938-1939
1938
1938
1940
circa 1940
1801-1892 (prepared); 1946 (element replaced)
4000-2001 BCE
1839 (original); circa 1988 (replica)
circa 1939
1940
1903 (original); 1982 (model)
1938
1938
1990-95
1940
1940
1938
1938-07-09
1940
1938
1938
circa 3000 BCE
1940
1939
2000 BCE
circa 1939