
Medal commemorating first free balloon stratospheric flight of Professor Auguste Piccard and Dr. Paul Kipfer
1931
1931
circa 1930
1931
1931
1930
circa 1930
1955; 1830
1931
2000-100 BCE
1930-1931
1934
1930
1929
1903 (original); 1982 (model)
1990-96
1830 (original); 1967 (model)
1952-3
1930
1839 (original); circa 1988 (replica)
1931
1930
1931
4000-2001 BCE
1930
1930 (replica); 1834 (original)
1801-1892 (prepared); 1946 (element replaced)
1934
1834-1836
1929
1930s
1940-03
circa 1931
circa 1931
1931
1942-09
1942-07
1942-07
1939-02
1931-11-12
1963-01
1931-11-23
1931-09-06
1938-10
1947-04
1940-01
1946-01
1955-10
1947-05
1931-04-16
1960-01