Medal commemorating first free balloon stratospheric flight of Professor Auguste Piccard and Dr. Paul Kipfer
1931
1931
1930
circa 1930
1931
1931
1955; 1830
circa 1930
circa 1930
1934
2000-100 BCE
1930-1931
1930
1930 (replica); 1834 (original)
1930
1929
1903 (original); 1982 (model)
1990-96
1929
circa 1929
1930
1930
1934
1830 (original); 1967 (model)
1930
1931
1931
4000-2001 BCE
1801-1892 (prepared); 1946 (element replaced)
1931
circa 1930s
1930s
circa 1931
1930s
circa 1930s
circa 1931
circa 1930s
1930s
circa 1930s
circa 1930
circa 1930s
circa 1930s
circa 1931
1931
1929
circa 1930s
1930
1962-05
1931
circa 1930s
circa 1931