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