Combined graphometer and plummet clinometer, 1663.
1663
1663
1932-1936
1936
circa 1976
1920s
1958-1965
circa 1920
circa 1922
1938
circa 1950
c. 1920
1922
1911-1915
circa 1922
circa 1920
1920s
1915-1925
1677
1923-5
circa 1914
circa 1914
1907-1917
1950-1952
circa 1922
1935
circa 1910
1918
circa 1924
circa 1920
circa 1914
circa 1912
circa 1910
circa 1910
1915-1925
1929
circa 1920
circa 1960
circa 1920
circa 1914
circa 1930s
1915
circa 1954
circa 1930s
1922
1876
circa 1914
circa 1925
1860-1888