Thermo galvanometer
![Thermo Galvanometer made by Cambridge Scientific Instrument Company Ltd.](/Images/godic/202502/16/Cambridge_Thermo_Galvanometer_19055746.jpg")
The thermo-galvanometer is an instrument for measuring small electric currents. It was invented by William Duddell about 1900. The following is a description of the instrument taken from a trade catalog of Cambridge Scientific Instrument Company dated 1905: