Report issued by the Bureau of Mines over diesel engine operations. As stated in the introduction, "it is the purpose of this report to present such data and to reemphasize the importance of adequate maintenance for diesel engines used underground" (p. 2). This report includes tables, and illustrations.

Report and corollary maps on the Coyote Mesa District, Dolores Plateau Area, Colorado

Report issued by the U.S. Bureau of Mines on the investigative and educational work done by the Safety Division during 1942. Accident prevention methods and safety incentives are presented. These include first-aid and mine rescue training programs. This report includes tables, and photographs.

Introduction: Vanadium ore is being mined at many places in western Colorado, southeastern Utah, northeastern Arizona, and northwestern New Mexico (fig. 1). Eight mills in this region produced about 4,300,000 pounds of V2 05 in 1942, representing about 90 percent of the vanadium obtained from domestic sources. Although ore production has mostly exceeded mill capacity since 1937, production during the last half of 1942 averaged only about 19,000 tons or ore a month, whereas the capacity of these mills total about 22,000 tons a month. At the expected rate of ore production, ore stockpiles will be exhausted sometime in 1944, and these mills will then have excess capacity. With more intensive prospecting than now practiced, however, it is believed that sufficient reserves can be indicated to sustain capacity operation of these mills for several years. This memorandum is prepared to specify those areas that are considered most favorable from a geologic standpoint for developing large reserves of vanadium ore by prospecting. It is based on intensive studies by the Geological Survey since 1939 in most of the areas that produce vanadium ore.

The following report was written to replace previous directions submitted in the February 6, 1943 report on the preparation of the solution X(OC₂H₅)₅.

The resonance absorption of uranium for neutrons has been investigated between 20 degree C and 1000 degree C. Experiments were caried out on both UO2, density 4.63, and metal. The resonance activity was measured with respect to that of an iodine monitor at several different temperatures and the ratio of activity at temperature T to that at 20 degree C was determined. The increase in activity is 0.9 per cent per 100 degree C for the oxide and 1.1 percent per 100 degree C for the metal. The period of U239 was found to be 23.54 +- 0.05 min.