An experimental high temperature high vacuum furnace with self-supported tungsten resistance heating elementsis described. The furnace is assembled from readily obtainable parts, and knife-edge vacuum seals are used through-out.The volume of the hot chamber is approximately 2 in. diameter by 8 in. high; the uniform zone is 2 in. long.A temperature of 2000°C can be attained at a pressure of∼10−5 mm Hgand at a power expenditure of 12 kw.