Cracking plant No51, a modified atmospheric distillation operation, was conducted from July 21 to 23, 1952 for several purposes. It was desired to prepare a supply of fresh heavy gas oil for charging to a future Suspensoid cracking operation, and also to prepare certain quantities of asphalt and road oil cutter stock for blending several MC-grade road oils. The latter materials were for use in a station road surfacing project.