
Perkin-Elmer F17 Gas Chromatograph, c. 1965
circa 1965
circa 1965
circa 1969
1980
1967
1967
1971
circa 1980
1978
1962
1960
circa 1980
circa 1971
circa 1980
circa 1958
1980s
1968
1955-1965
1970-1980
1975-1990
1980
1979
1970-1996
circa 1972
1982
1966
1985
circa 1980
1970s
1950
circa 1990
1961
1961
1970
1944-1950
1951
circa 1974
1965-1975
1970
1960-1963