Medal commemorating first free balloon stratospheric flight of Professor Auguste Piccard and Dr. Paul Kipfer
1931
1931
1935
1935
1931
1935
1934
1931
1935
1932
1955; 1830
1934
1935
1932
1933
1934
1935
1932
2000-100 BCE
Before 1932
1934
1935
1933
1935
1934
1933
1935
1935
1935
1903 (original); 1982 (model)
1933
1933
1934
1990-96
1934
Before 1932
1935
1932-1933
1934
1935
1830 (original); 1967 (model)
1935
1931
1935
1931
4000-2001 BCE
1801-1892 (prepared); 1946 (element replaced)
1931
1935
1932
circa 1931