In Refining Unit Report No. 1 the initial operations of the oil-shale demonstration cracking plant were described. These operations began in July and extended through September 1949. They consisted of atmospheric, visbreaking, and recycle cracking runs, The atmospheric and visbreaking runs were hampered by the usual difficulties incident to starting up new equipment. The data obtained during these runs therefore were not felt to be entirely reliable. The recycle cracking runs which followed were not similarly hampered, and the data obtained were more detailed and conclusive.