ABS>The physical and chemical properties of lithium hydride are described, based on reasonably full coverage of the available unclassified literature as of July 1, 1960. Where possible, the data are presented critically. Lithium deuteride and lithium hydride gases are included. Practical matters such as thermal stability, corrosive character, utilization, handling, fabrication, and analysis are discussed. This report replaces report NYO-3957 and its supplement NYO-8022. 230 references. (auth)