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Revision of the Pocket Mice of the Genus Perognathus

Description: Revision of earlier report in this series detailing changes in classification resulting from study of up to 3,000 specimens.
Date: September 20, 1900
Creator: Osgood, Wilfred H.
Partner: UNT Libraries Government Documents Department

Revision of the Spiny Pocket Mice: (Genera Heteromys and Liomys)

Description: From introduction: "Result of a study of the spiny pocket mice in the collection of the Biological Survey, now numbering nearly 1,000 specimens, supplemented by about 130 in the United States National Museum and from various sources."
Date: September 7, 1911
Creator: Goldman, Edward A.
Partner: UNT Libraries Government Documents Department

Fuel-Briquetting Investigations, July, 1904, to July, 1912

Description: Report discussing a series of fuel-testing investigations that U.S. Geological Survey began in 1904 for the purpose of analyzing and testing the coals and lignites in the United States in order to determine their fuel values and the most efficient methods of utilizing them for different purposes. Types of tests undertaken included chemical analyses, steaming tests, gas-producer tests, briquetting tests, coking tests, and washing tests of samples collected from the various coals fields of the country. Bulletins presenting the results of these investigations have been periodically published but as supply has run out, the Bureau of Mines has decided to compile the most important facts of these bulletins in one volume along with the results of all other briquetting investigatins undertaken by the government from July 1, 1904, to July 1, 1912.
Date: September 1913
Creator: Wright, C. L.
Partner: UNT Libraries Government Documents Department

Metallurgical Coke

Description: Technical paper issued by the Bureau of Mines over studies on metallurgical coke. As stated in the introduction, "in this paper the attempt is made to summarize the history of coke making in the United States, to indicate the development of different methods and the modern types of ovens, and to point out the composition and physical properties of the metallurgical cokes produced in this country" (p. 5). This paper includes tables, illustrations, photographs, and a map.
Date: September 1913
Creator: Belden, A. W.
Partner: UNT Libraries Government Documents Department

Life Zones and Crop Zones of New Mexico

Description: Discusses geography, climate, agricultural practices, and crops of each life zone in New Mexico. Provides mammal, breeding bird, reptile, amphibian, and plant species list for each zone. Includes a life zone map.
Date: September 5, 1913
Creator: Bailey, Vernon
Partner: UNT Libraries Government Documents Department

A Review of the American Moles

Description: Discusses habits; economic status; characteristics and development of young; pelages and molts; and geographic, individual, sexual, and age variation. Describes subfamilies, history, and generic names of the family Talpidae. Describes, lists locations, and provides a key for genera, species and subspecies.
Date: September 30, 1915
Creator: Jackson, Hartley H. T.
Partner: UNT Libraries Government Documents Department

Prospecting and Mining of Copper Ore at Santa Rita, New Mexico

Description: Report discussing techniques for the mining of large masses of low-grade ores such as though found in Santa Rita, NM. It is hoped that a study of the methods used at Santa Rita will help engineers in other industries who may have to handle large masses of material.
Date: September 1916
Creator: MacDonald, Donald F. & Enzian, Charles
Partner: UNT Libraries Government Documents Department

An Introduction to the Laws of Air Resistance of Aerofoils

Description: Report presents methods of calculating air resistance of airfoils under certain conditions of flow phenomena around the airfoil.
Date: September 1918
Creator: de Bothezat, George
Partner: UNT Libraries Government Documents Department

The Rice Rats of North America (Genus Oryzomys)

Description: Discusses habits, economic status, morphology, variation, history, and specimens of North American rice rats. Provides a key and descriptions for species and subspecies.
Date: September 23, 1918
Creator: Goldman, Edward A.
Partner: UNT Libraries Government Documents Department

Drag or Negative Traction of Geared-Down Supporting Propellers in the Downward Vertical Glide of a Helicopter

Description: Discussed here are computations of drag or negative traction of geared down supporting propellers in the downward vertical glide of a helicopter. By means of Frounde's Theory, the maximum value of the drag of a windmill is calculated. For wooden propellers, the author finds that the difference between the drag and the weight is proportional to the number of blades and is larger for propellers of small diameter; thus it is 25 kg. for a six blade propeller with a diameter of 2 m. 50.
Date: September 1920
Creator: Toussaint, A.
Partner: UNT Libraries Government Documents Department

The Dynamometer Hub

Description: The construction of the dynamometer hub is illustrated and explained, and its electrical and aviation motor tests, as well as those in free flight, described.
Date: September 1920
Creator: Stieber, W.
Partner: UNT Libraries Government Documents Department

Experience With Geared Propeller Drives for Aviation Engines

Description: An overview is given of experience with geared propeller drives for aviation engines. The development of gear wheels is discussed with emphasis upon bending stresses, compressive stresses, heating, and precision in manufacturing. With respect to the general arrangement of gear drives for airplanes, some principal rules of mechanical engineering that apply with special force are noted.
Date: September 1920
Creator: Kutzbach, K.
Partner: UNT Libraries Government Documents Department

Recent Efforts and Experiments in the Construction of Aviation Engines

Description: It became evident during World War I that ever-increasing demands were being placed on the mean power of aircraft engines as a result of the increased on board equipment and the demands of aerial combat. The need was for increased climbing efficiency and climbing speed. The response to these demands has been in terms of lightweight construction and the adaptation of the aircraft engine to the requirements of its use.
Date: September 1920
Creator: Schwager, [Otto]
Partner: UNT Libraries Government Documents Department

The 1000 HP Traffic Airplane of the Zeppelin Works in Staaken

Description: Report details the characteristics and advantages of the swift traffic airplane constructed by Zeppelin Works at Staaken. The maximum speed, weight, construction, layout, and landing capabilities of the plane are included.
Date: September 1921
Creator: Rohrbach, A. K.
Partner: UNT Libraries Government Documents Department

Competition for Safety Fuel Tanks

Description: Report describing a competition for safety fuel tanks, including the prizes, requirements that must be fulfilled, some other characteristics, tests, and regulations.
Date: September 1921
Partner: UNT Libraries Government Documents Department

The Effect of Staggering a Biplane

Description: This investigation was carried out by request of the United States Air Service at the Massachusetts Institute of Technology wind tunnel in 1918. As the data collected may be of general interest, they are published here by the National Advisory Committee for Aeronautics. The lift, drag, and center of pressure travel are determined for a biplane with a stagger varying from +100% to -100%. It is found that the efficiency and the maximum lift increase with positive stagger.
Date: September 1921
Creator: Norton, F. H.
Partner: UNT Libraries Government Documents Department

Lift Theory of Supporting Surfaces: Second Article

Description: Memorandum presenting a description of the hydrodynamic lift theory of supporting services. This report is mainly about the task of finding suitable wing sections for given lift conditions. Formulas are given for lift magnitude and moment, which make it possible to obtain solutions of great simplicity and clearness.
Date: September 1921
Creator: von Mises, R.
Partner: UNT Libraries Government Documents Department

A New Dynamometer Brake

Description: The mechanism here described belongs to the class of dynamometer brake in which the motive power is transformed into heat in the brake itself. This mechanism was invented by the writer for the purpose of measuring forces in which the two factors, torque and speed, vary within broad limits, the mechanism itself being of simple construction and of still simpler operation.
Date: September 1921
Creator: Segrè, Marco
Partner: UNT Libraries Government Documents Department

Performance of a vane driven-gear pump

Description: Given here are the results of a test conducted in a wind tunnel on the performance of a vane-driven gear pump used to pump gasoline upward into a small tank located within the upper wing from which it flows by gravity to the engine carburetor. Information is given on the efficiency of the pump, the head resistance of the vanes, the performance and characteristics of the unit with and without housing about the vanes, the pump performance when motor driven, and resistance and power characteristics.
Date: September 1921
Creator: Heald, R. H.
Partner: UNT Libraries Government Documents Department