"Engineering was continued on the development of sodium cooled, graphite moderated type reactors. General studies were carried out as well as studies specifically devoted to the following: a. full scale poser-only plant, b. thirty-mega watt pilot plant, the SGR, c. sodium reactor experiment, the SRE. This work consisted of theoretical analysis of various aspects of nuclear performance; economic investigations of different fuel element, cooling system and plant arrangements; and experimental investigations related to the properties of certain materials and to the development of components. Preliminary consideration was given to alternative reactor arrangements employing liquid hydrocarbon moderators and high temperature coolants other than sodium. In addition to a summary of the general design features of the SRD, a program was prepared outlining the proposed use of this installation.