Whirling psychrometer for measuring humidity
1950-1953
Clockwork aspirated psychrometer
Psychrometer by Casella
Whirling psychrometer
1920-1940
Assmann psychrometer
1922
August psychromete
1876
Clockwork psychrometer by R. Fuess
1938
Assmann psychrometer by C. F. Casella
1919
Aspirated psychrometer by Casella
1930
Clockwork aspirated psychrometer by Casella
1950-1970
Whirler for psychrometer, c. 1918.
1918
Aspirated electric psychrometer
1997
Comins electro-psychrometer by the American Moistening Co.
1910
Clockwork psychrometer
1935-1945
Assmann psychrometer by Casella
1944
Wet bulb in aircraft psychrometer housing, 1940s.
1940-1950
Whirling psychrometer
1950-1960
Strut psychrometer Mk VA wet and dry bulb alcohol in glass Fahrenheit thermometers
Clockwork aspirated psychrometer, Mk3
1971
Air Psychrometer Mark V, with aircraft wing strut mounting straps
Casing for clockwork psychrometer
1940-1950
Psychrometer scale, of paper on wooden frame.
Direct reading psychrometer
1924
Pair of Mercury thermometer for hygrometer, British, 1866
1866
Aeroplane psychrometer Mark II
1818-1922
Clockwork and fan for psychrometer by Salmoiraghi
1940-1950
Strut psychrometer
1930
Assmann psychrometer by Friedrichs & Co
1950-1960
M.O. Balloon psychrometer
1945
Strut psychrometer Mark VB
1943
Regnault type hygrometer with mercury thermometer
1866
Wet and dry bulb hygrometer, British, 1986
1986
Aircraft strut psychrometer
1927
Part of Regnault type hygrometer, British, 1866
1866
Aeroplane psychrometer Mark II, 1918-1922.
1918-1922