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