“…Techniques and apparatus have been developed which make singlecrystal X-ray investigations of such compounds feasible down to the temperature of liquid air (Kaufman & Fankuchen, 1949;Abrahams, Collin, IApscomb & Reed, 1950;Post, Schwartz & Fankuchen, 1951). In this paper the determination of the crystal structure of sulfur dioxide, using these techniques, is described.…”