
Rubber vault cap
1938-1940
1938-1940
1839 (original); circa 1988 (replica)
1936
1935
1830 (original); 1967 (model)
1903 (original); 1982 (model)
1935
1937
1937
1935
1940
circa 1938
1938
1938
1938
1938
1938
1940
1955; 1830
1935
1939
1936
1938 and 1951
1935
1936
2000-100 BCE
1937-1937
1937-1938
1937-1938
1938
1936
1940
1938
1938
1935
1935
1939
1801-1892 (prepared); 1946 (element replaced)
1938
1940
1938
1940
circa 1940
1938
1937
1936
1937
1935
1938
1938