Double surface of revolution of constant negative curvature
1910
1910
1910
circa 1910
1934
1906
circa 1905
1908
1904
1909
1905
1906
1904
1904
1910
2000-100 BCE
1906
1872 (original); 1909 (model)
1955; 1830
1910
1910
1907
1905
1990-96
1904
1905
1934
1930 (replica); 1834 (original)
1801-1892 (prepared); 1946 (element replaced)
1905
1907
1705-1737
1905
1904
1903 (original); 1982 (model)
1772 (original); 1919 (model)
1830 (original); 1967 (model)
4000-2001 BCE
1909
1906
1909-1910
1910
1908
1908-1900
circa 1904
1910
1971-1900
17th July 1905
17th July 1905
17th July 1905
17th July 1905