Tube Furnace: Porcelain Tube Wound with Platinum Wire in a Heat-Retaining Jacket (Stansfield, 1914)

The laboratory tube furnace: a porcelain tube wound with a spiral of platinum wire and wrapped in a heat-retaining jacket. Current through the wire heats the tube and whatever is inside it. A gas can be passed through the tube, the work watched through windows at the ends, and the temperature read with a thermocouple pushed in from one end. Result: a small furnace for heating a material in any chosen gas at moderate temperatures, well short of platinum's melting point. Source: A. Stansfield, The Electric Furnace: Its Construction, Operation and Uses (2nd ed., 1914), pp. 24-25 and 154. Unknown: sizes, the jacket material, current and voltage. Picture: Stansfield, Fig. 13.