Report issued by the Bureau of Mines on the development of efficient mining methods for producing oil shale. Characteristics of the oil shale deposits of the Green River are presented. The results of core drilling and sampling in this area are also listed. This report includes tables, illustrations, maps, and photographs.

Report presenting a flight test of a supersonic research pilotless aircraft in which large-amplitude aileron oscillations, most likely aileron compressibility flutter, were encountered in the transonic and supersonic speed ranges. Results regarding power-on flight and coasting flight are provided.

"Methods are presented that use general correlative time-response input and output data for a linear system to determine the frequency-response function of that system. These methods give an exact description of any linear system for which such transient data are available. Examples are shown of application of a method to both an underdamped and a critically damped exact second-order system, and to an exact first-order system with and without dead time. Experimental data for a turbine-propeller engine showing the response of engine speed to change in propeller-blade angle are presented and analyzed" (p. 547).

"A general algebraic method of attack on the problem of controlling gas-turbine engines having any number of independent variables was utilized employing operational functions to describe the assumed linear characteristics for the engine, the control, and the other units in the system. Matrices were used to describe the various units of the system, to form a combined system showing all effects, and to form a single condensed matrix showing the principal effects. This method directly led to the conditions on the control system for noninteraction so that any setting disturbance would affect only its corresponding controlled variable" (p. 581).

Monthly magazine discussing natural resources, parks, hunting and fishing, and other information related to the outdoors in Texas.

Monthly magazine discussing natural resources, parks, hunting and fishing, and other information related to the outdoors in Texas.

Annual report submitted by the Boy Scouts of America to Congress describing highlights from 1939, activities, finance, honors, service reports, organizational leadership, and other information about scouting programs.