Combined graphometer and plummet clinometer, 1663.
1663
1663
circa 1930s
1886
1860-1888
1911
1876
1677
1911-1915
1936
1932-1936
1902
1935
circa 1976
circa 1930s
circa 1930s
1860-1888
circa 1935
circa 1910
1924
1958-1965
circa 1954
circa 1924
circa 1918
circa 1956
circa 1932
1915-1925
1961-1965
1925-1940
1935
1910-1914
1931
1935
1967
1936
1935
1920-1930
1922-25
1967
1910
1920
1910-1930