Langley's 'Great' Bolometer, 1880-1890
1880-1890
Edison's Original Micro-Tasimeter, 1878
1878
Boys' Radiomicrometer, 1887-1900
1887-1900
Callendar's Disc 'Radio-Balance', 1905-1920
1905 (invented); 1907-1920
Callendar's Bolometer, 1914
1914
Langley's Bolometer, 1880-1890
1880-1890
Callendar's Original Radio Balance, 1905-1906
1905-1906
Callendar's Absolute Recording Bolometer, 1905
1905
Original Cup Radio-Balance by H. L. Callendar, 1910
1910