The hydrothermal equipment consists of 10 vertical cold-seal pressure vessels (bombs) with split tube furnaces. The bomb consists of a cooled lower end separated to the hot upper part by the water-cooled connection. The magnet holds the experimental charges in the hot part of the bomb. The charge is lowered into the cold part at the end of the experiment. This provides a safe quenching of the experiments to room temperature in a view seconds. External NiSil-thermocouples accurately measure temperature and permit control during the hydrothermal experiments. Heating rates and temperature are continuously recorded by a computer. The pressure medium is either argon or nitrogen. Currently our system is designed for temperatures up to 850° and a pressure of 2kbar.