Langley's Bolometer, 1880-1890
1880-1890
Langley's 'Great' Bolometer, 1880-1890
1880-1890
Callendar's Bolometer, 1914
1914
Model of Callendar's Sunshine Receiver, 19th Century
1895-1910
Callendar's Absolute Recording Bolometer, 1905
1905