A simple pressure vessel to contain inert gas at pressures up to 60 MN m$minus$2 and a maximum temperature of 850$deg$C

Special features of the design and construction of a small internally heated pressure vessel with a working volume of 30 cm 3 are briefly described and an indication is given of its usefulness over a range of research topics. The adaptation of commercially available heating elements simplifies the pressure vessel design and use, and provides an internal furnace with rapid response. The satisfactory performance of all features of the equipment has been established in continual use in more than 100 experiments with a total operating time of 2000 hours.