Memorandum presenting an analysis of a large number of liquid-metal-to-air heat-exchanger cores for the nuclear-powered liquid-metal turbojet cycle to determine which types yield the best overall net thrust per total engine weight. The performances of all exchangers considered were initially evaluated at a median condition. The performance of the best of each of the four types was compared with that of a shell-and-tube exchanger with the air flowing through the tubes, operating at the same condition.

Report issued by the Bureau of Mines over studies conducted on manganese deposits of Aroostook County, Maine. Descriptions of the deposits, and the results of the study are presented. This report includes tables, maps, illustrations, and photographs.