Submitted as a thesis by William Berdell Barlage, Jr. Heat transfer studies were refined and extended to the point where the results could be generalized into a mathematical correlation valid over a reasonably wide range of variables. An extended study was made of the rate of heat transfer between benzene and water in direct contact in a pulse column, and of the operating variables which controlled the behavior. In this mode of heat transfer the benzene was dispersed as a family of droplets into the water, which formed the continuous phase. The pulse column was 1.92-in. in inside diam., and contained 8 stainless steel perforated plates spaced 2.00 inches apart. The plates were perforated with 1/8-in. holes in a triangular 60 deg pattern, providing 24.6 per cent free area. The equipment was carefully insulated and modified in many details in order to permit precise heat transfer measurements. The operating conditions were varied so as to provide wide ranges of variables and heat transfer responses. (W.L.H.)