From Ralph Hancock
The small thermocouple-powered generator described by Duncan Graham-Rowe is not all that new (21 September, p 21). In the 1930s and 1940s, the Russians used a simple thermoelectric device to power valve radios in areas where there was no electricity supply. It consisted of a zigzag array of thermocouples arranged in a circle around the flame of a paraffin lamp, making the inner junctions hotter than the outer ones.
The attached picture, from a magazine I edited, is a redrawing of an old Soviet press agency picture that was too blurred to print. The press release did not mention which two metals were used in the thermocouples.
London
