
Obsidian possibly used in trephination experiments
1918-1920
1918-1920
1903
1901-1920
1903
1918
1920-1925
1952-3
1905
1830 (original); 1967 (model)
circa 1919
1915-1925
1919
1923
1801-1840 (original); 1901 (model)
1923
1910-1923
1911
1917
1902
1901-1910
1915-1918
1920
1914-1916
1909-1910
1913
circa 1915
1901-1920
1915-1918
1668; 1924
1610; 1923
circa 1923
circa 1925
1907
1901
1904
1910
1915
1920
1915
1924
1910
1908
1901
1918
1904
circa 1910
1914-1920
1909
1910
1922