Earth thermometer with bent stem, c. 1925.
1925
1925
1985
1943
1964
1985
1880-1889
1997
1952
1985
1985
1966
1986
1985
1985
1985
1985
1874
1874
1950-1959
1950-1959
1874
1968
1960-1969
1966
1971
1917
1943
1968
1925
1997
1972
1964
1925
1944