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Revision of the North American Pocket Mice: From introductory remarks: "Classification study of the North American pocket mouse based on about 170 specimens. Results of study increased recognized species to 18 and subspecies to 3 as well as shifting several well known names to other forms."
Electrolysis and its Mitigation: Technical paper issued by the Bureau of Standards over studies conducted on electrolysis. As stated in the introduction, "this investigation has included a study of the physical laws governing electrolytic and self-corrosion in soils, an extended investigation of the effects of electric currents on plain and reinforced concrete, and a study of the work of previous investigators relating to the subject of electrolysis and its prevention" (p. 5). This paper includes tables, illustrations, and photographs.
Comparison of Alcogas Aviation Fuel With Export Aviation Gasoline: Mixtures of gasoline and alcohol when used in internal combustion engines designed for gasoline have been found to possess the advantage of alcohol in withstanding high compression without "knock" while retaining advantages of gasoline with regard to starting characteristics. Test of such fuels for maximum power-producing ability and fuel economy at various rates of consumption are thus of practical importance, with especial reference to high-compression engine development. This report discusses the results of tests which compares the performance of alcogas with x gasoline (export grade) as a standard.
Endurance Tests of Tires: Technical paper issued by the Bureau of Standards over studies conducted on the endurance of tires. 230 tires of 36 different brands were tested during the studies. The results of the studies are presented and discussed. This paper includes tables, and photographs.
The relative performance obtained with several methods of control of an overcompressed engine using gasoline: "This report presents some results obtained during an investigation to determine the relative characteristics for several methods of control of an overcompressed engine using gasoline and operating under sea-level conditions. For this work, a special single cylinder test engine, 5-inch bore by 7-inch stroke, and designed for ready adjustment of compression ratio, valve timing and valve lift while running, was used. This engine has been fully described in NACA-TR-250. Tests were made at an engine speed of 1,400 R. P. M. for compression ratios ranging from 4.0 to 7.6" (p. 329).
The N.A.C.A. photographic apparatus for studying fuel sprays from oil engine injection valves and test results from several researches: "Apparatus for recording photographically the start, growth, and cut-off of oil sprays from injection valves has been developed at the Langley Memorial Aeronautical Laboratory. The apparatus consists of a high-tension transformer by means of which a bank of condensers is charged to a high voltage. The controlled discharge of these condensers in sequence, at a rate of several thousand per second, produces electric sparks of sufficient intensity to illuminate the moving spray for photographing. The sprays are injected from various types of valves into a chamber containing gases at pressures up to 600 pounds per square inch" (p. 361).
The Gaseous Explosive Reaction: A Study of the Kinetics of Composite Fuels: "This report deals with the results of a series of studies of the kinetics of gaseous explosive reactions where the fuel under observation, instead of being a simple gas, is a known mixture of simple gases. In the practical application of the gaseous explosive reaction as a source of power in the gas engine, the fuels employed are composite, with characteristics that are apt to be due to the characteristics of their components and hence may be somewhat complex" (p. 503).
Working Charts for the Selection of Aluminum Alloy Propellers of a Standard Form to Operate With Various Aircraft Engines and Bodies: "Working charts are given for the convenient selection of aluminum alloy propellers of a standard form, to operate in connection with six different engine-fuselage combinations. The charts have been prepared from full-scale test data obtained in the 20-foot propeller research tunnel of the National Advisory Committee for Aeronautics. An example is also given showing the use of the charts" (p. 3).
Comparative flight performance with an NACA Roots supercharger and a turbocentrifugal supercharger: This report presents the comparative flight results of a roots supercharger and a turbocentrifugal supercharger. The tests were conducted using a modified DH-4M2 airplane. The rate of climb and the high speed in level flight of the airplane were obtained for each supercharger from sea level to the ceiling. The unsupercharged performance with each supercharger mounted in place was also determined. The results of these tests show that the ceiling and rate of climb obtained were nearly the same for each supercharger, but that the high speed obtained with the turbocentrifugal was better than that obtained with the roots. The high-speed performance at 21,000 feet was 122 and 142 miles per hour for the roots and turbocentrifugal, respectively.
The effect on airplane performance of the factors that must be considered in applying low-drag cowling to radial engines: From Summary: "This report presents the results of flight tests with three different airplanes using several types of low-drag cowling for radial air-cooled engines. The greater part of the tests were made with a Curtiss XF7Cc-1 (Sea Hawk) with a 410 horsepower. Wasp engine, using three fuselage nose shapes and six types of outer cowling. The six cowlings were: a narrow ring, a wide ring, a wide cowling similar in the original NACA cowling, a thick ring incorporating an exhaust collector, a single-surface cowling shaped like the outer surface of the exhaust-collector cowling, and polygon-ring cowling, of which the angle of the straight sections with the thrust line could be varied over a wide range."
Preliminary Investigation of Modifications to Conventional Airplanes to Give Nonstalling and Short-Landing Characteristics: "This report describes flight and landing tests made on a group of conventional airplanes. The upward deflection of the elevators was limited to the point where the airplanes could not be made to spin without the aid of power. With the elevator travel thus limited, the airplane in every case had good lateral stability and good aileron effectiveness up to the highest angles of attack which could be obtained in a glide, although this was not true in any case without the limited control" (p. 343).
Some Effects of Argon and Helium Upon Explosions of Carbon Monoxide and Oxygen: Report presents the results of an investigation conducted to study the effects of the inert gases, argon and helium, upon flame speed and expansion ratio in exploding mixtures of carbon monoxide, oxygen and water. For the particular gas mixtures investigated the results show that: (1) With the possible exception of helium in small amounts the addition of inert gas always produces decreased flame speed and expansion ratio; (2) like volumes of argon and helium have very different effects upon flame speed but practically the same effect upon expansion ratio; and (3) the difference in the effect of these two gases upon speed is independent of the ratio of carbon monoxide to oxygen. A discussion of some possible modes by which inert gases may produce the observed effects is included.
Wind-Tunnel Investigation of Ordinary and Split Flaps on Airfoils of Different Profile: Report presents the results of wind tunnel tests of the Clark Y, the NACA 23012 and the NACA 23021 airfoils equipped with full-span ordinary flaps and with full-span simple split flaps. The principal object of the tests was to determine the characteristics of the airfoils with ordinary flaps and in addition, to determine the relative merits of the various airfoils when equipped with either ordinary flaps or with simple split flaps. The Clark Y airfoil was tested with 3 widths of ordinary flap, 10, 20, and 30 percent of the airfoil chord.
Calculated and measured pressure distributions over the midspan section of the NACA 4412 airfoil: Pressures were simultaneously measured in the variable-density tunnel at 54 orifices distributed over the midspan section of 5 by 30 inch rectangular model of the NACA 4412 airfoil at 17 angles of attack ranging from -20 degrees to 30 degrees at a Reynolds number of approximately 3,000,000. Accurate data were thus obtained for studying the deviations of the results of potential-flow theory from measured results. The results of the analysis and a discussion of the experimental technique are presented.
Heat Transfer to Fuel Sprays Injected Into Heated Gases: This report presents the results of a study made of the influence of several variables on the pressure decrease accompanying injection of a relatively cool liquid into a heated compressed gas. Indirectly, this pressure decrease and the time rate of change of it are indicative of the total heat transferred as well as the rate of heat transfer between the gas and the injected liquid. Air, nitrogen, and carbon dioxide were used as ambient gases; diesel fuel and benzene were the injected liquids. The gas densities and gas-fuel ratios covered approximately the range used in compression-ignition engines. The gas temperatures ranged from 150 degrees c. to 350 degrees c.
Fuel spray and flame formation in a compression-ignition engine employing air flow: "The effects of air flow on fuel spray and flame formation in a high-speed compression-ignition engine have been investigated by means of the NACA combustion apparatus. The process was studied by examining high-speed motion pictures taken at the rate of 2,200 frames a second. The combustion chamber was of the flat-disk type used in previous experiments with this apparatus. The air flow was produced by a rectangular displacer mounted on top of the engine piston. Three fuel-injection nozzles were tested: a 0.020-inch single-orifice nozzle, a 6-orifice nozzle, and a slit nozzle" (p. 281).
Static Thrust and Power Characteristics of Six Full-Scale Propellers: "Static thrust and power measurements were made of six full-scale propellers. The propellers were mounted in front of a liquid-cooled-engine nacelle and were tested at 15 different blade angles in the range from -7 1/2 degrees to 35 degrees at 0.75r. The test rig was located outdoors and the tests were made under conditions of approximately zero wind velocity" (p. 85).
Theory of ballooning.: A general guide to piloting a free balloon.
Ordnance maintenance : 3-inch antiaircraft gun matériel, M2A2, M2A1, M1A2, M1A1, T1A2, and T1A1: Provides instructions for inspection, disassembly and assembly, and maintenance and repair of 3-inch antiaircraft gun matériel, including the use of special repair tools.
Chemical Properties of Uranium Hexafluoride, UF6: Uranium hexafluoride has the distinction of being the only stable gaseous compound of uranium known up to the present moment. Because of this property it is the only compound that can be used for processes of isotope separation, such as diffusion, thermal diffusion, centrifuge separation, distillation, and other of a similar nature. Here is a short description of the properties of UF{sub 6} and is intended for a reader interested only casually in this compound. UF{sub 6} is a very reactive compound and a very strong fluorinating agent. It is immediately hydrolized by water. In fluorinating reactions it is reduced to the green highly stable UF{sub 4}. It reacts instantaneously with hydrogen at room temperature. It fluorinates many metals; sodium and mercury are attacked in the cold, lead, zinc, tin and iron on heating; platinum and gold react only above 400 C. With organic compounds like alcohol, ether, benzene or toluene, immediate fluorination takes place with formation of HF and carbon or carbonaceous material. The compound forms colorless, very volatile, beautiful transparent crystals of high refractive index. Melting point = 69.5{sup o}; boiling point at 760 mm = 56.2{sup o}; D20{sup o} = 4.68. The crystals melt water pressure to a transparent colorless liquid of high density, but great mobility.
Newsmap. Monday, May 25, 1942 : week of May 15 to May 22: Front : Text describes action on various war fronts: Axis hunts Shangri La -- Shadow on Australia -- New threat to China -- Gandhi still passive -- More Yanks in Ireland -- U.S. gets Panama bases -- Spain would trade -- Island volcano erupts -- Axis people grumble -- Axis battles Chetniks -- Air travel curtailed -- Prinz Eugen torpedoes -- Attack on Kharkov -- Vichy downs RAF planes -- Africa drive hinted -- Malta counts bombings. Large world map is keyed to text and illustrates time zones around the world. Inset maps show the Burma Road and a map of a portion of Europe overlaying a map of the United States. U.S. cities are shown in italics, European cities in capitals. Includes photographs: Doolittle did much -- North American B-25 -- Gandhi opposes [scorched earth policy] -- School of 'tin fish' ready for their deadly work -- Shell casings stacked in Moscow factory -- Rommel might move -- Catalinas from America keep an eye on the Mediterranean -- RAF salvages wrecked planes from desert. Includes 1 cartoon. Back: Know Your Enemies: the Nazi Army. Includes photographs: Supporting Fire, Howitzer in Action, Moving Up, Mountain Troops, Tank Destroyer, Anti-Aircraft Alert, No. 2 Man, Quick Crossing, Battle Practice, Flame Thrower, Mopping Up. Inset has text details for each photograph.
Effect of Normal Pressure on the Critical Compressive Stress of Curved Sheet: Results are presented of tests of two specimens tested to study the effect of normal pressure on the critical compressive stress for thin curved sheets. These specimens are designated by their respective rib spacings of 10 inches and 30 inches. The relationship between compressive stress and normal pressure at which buckles disappeared is independent of whether the buckles were made to disappear by increase of normal pressure or decrease of compressive stress. (author).
Newsmap. Monday, January 25, 1943 : week of January 15 to January 22: Front: Text describes action on various war fronts: Tripoli, Western Europe, Guadalcanal, New Guinea, Pacific and Far East, Russia, Chile, Iraq. Large world map is keyed to text and illustrates time zones around the world. Inset maps: Tunisia/Libya ; Russian Front. Photographs: North Africa; Forward positions: Guadalcanal; Not in "Mein Kampf" [retreating German panzers struggling through mud]; Jap ships feel U.S. air blows. Back: Poster illustrating Italian Navy uniforms and insignia. Includes Italian pronunciation chart.
Density of Solid Hex Uf$Sub 6$ Near the Triple Point, and the Expansivity of the Liquid From the Triple Point to 92 C: The report addresses the density of solid hex near the Triple and the expansivity of the liquid from the triple point.
Physiological aspects of flying.: "The purpose of this manual is to endeavor to explain in everyday terms the various physical and physiological problems that arise during flying, and to give in detail the latest knowledge of proved solutions to these problems." (--Page 2.)
Newsmap. Monday, October 25, 1943 : week of October 14 to October 21, 215th week of the war, 97th week of U.S. participation: Front: Text describes action on various war fronts: Russia, Italy, Schweinfurt, Southwest Pacific, Burma, North Pacific, U.S. subs. Inset maps: Bridgeheads across the Dnepr River, [Pacific Ocean off coast of New Guinea], [Areas in Southern Europe providing targets for bomber forces], Operations begin in Burma. Photographs: Nazis use Soviet equipment and men in battle for Italy, Soviet soldier and RAF officer, Lieut. Col. Chesley G. Peterson, Salt Lake City, Fuel pipe lines, Fifth Army engineers, In the Naga Hills of northern Burma. Back: Photographic view of the world with the center at Berlin, Germany. Includes instructions for using a detachable scale that, when centered on Berlin, measures distances along any line running through Berlin.
Temperature Rise in a Heat Producing Cylinder Under a Coating Defect: Abstract: "For defects between interior and coating, or between successive layers of coating, a simple, fairly accurate formula is established. The temperature rise at the edge of the defect is briefly discussed."
Calculations for Some Pile Shapes of Which the Boundaries are Partly Spherical: Some methods for calculating the k requirements of various shaped piles are indicated, with particular reference to the shape of the tank in the homogeneous plant.
Eta Temperature Effect: The temperature coefficient of eta has been measured with the thermal column of the Argonne pile using uranium foils of different isotopic ratios. The temperature change was effected by filtering neutrons through silver. The measured fractional change per degree centigrade is [formula].
Intercooler cooling-air weight flow and pressure drop for minimum drag loss: An analysis has been made of the drag losses in airplane flight of cross-flow plate and tubular intercoolers to determine the cooling-air weight flow and pressure drop that give a minimum drag loss for any given cooling effectiveness and, thus, a maximum power-plant net gain due to charge-air cooling. The drag losses considered in this analysis are those due to (1) the extra drag imposed on the airplane by the weight of the intercooler, its duct, and its supports and (2) the drag sustained by the cooling air in flowing through the intercooler and its duct. The investigation covers a range of conditions of altitude, airspeed, lift-drag ratio, supercharger-pressure ratio, and supercharger adiabatic efficiency. The optimum values of cooling air pressure drop and weight flow ratio are tabulated. Curves are presented to illustrate the results of the analysis.
Thermopiles for pile monitoring: No Description Available.
Flight measurements of horizontal tail loads on a typical propeller-driven pursuit airplane during stalled pull-outs at high speed: Report presenting flight measurements of the pressures on the horizontal tail surfaces of a typical propeller-driven pursuit airplane during stalled pull-outs at high Mach number. Unit loads measured on the stabilizer at safe maneuvering limits were not only considerably in excess of the design unit loads, but also occurred in a direction opposite to the design loads. Revision of the tail-load design requirements and manner of specifying safe maneuverability limits to pilots appears necessary.
Photographic film as a pocket radiation dosimeter: The energy dependence of film blackening is discussed and shown graphically. The exposure range of films is discussed, and blackening is plotted vs exposure for DuPont No. 502, and for the less sensitive DuPont No. 351. A plan is then described for monitoring radiation exposure to workers by requiring the worker to carry an x-ray film of dental packet size in a badge designed for the purpose. (LEW)
Watermanship: "The purpose of this manual is three-fold: a. To give you those basic principles of watermanship that will enable you to meet with confidence any emergency that may arise. b. To teach you certain fundamental practices used during small landing-craft operations. c. To show you how to swim small lakes or rivers under combat conditions."
Eastern Black Shale Reconnaissance Preliminary Report: The following report is the result of a reconnaissance of the black shales of the Eastern United States in the summer of 1944. The purpose of this reconnaissance was to determine the radioactivity of the shales, specifically for uranium and thorium.
A Final Report on the Experiment : the Penetration of Graphite of Different Purities by Lead Bismuth Eutectic: Bi-Pb eutectic and pure Bi penetration of graphites of various densities under 300 degrees C and pressures up to 20 psi was found be of the order of magnitude of 1.0 g/cm(2) and was uniform throughout the graphite. Bi was absorbed less than the eutectic but the oxidation rate of Bi would be prohibitive. There was heavy nitriding in N atmospheres with the Bi and the eutectic.
Newsmap. For the Armed Forces. 263rd week of the war, 145th week of U.S. participation: Front: Text describes action on various war fronts: France, Pacific, Italy, China-Burma, Eastern front. Maps: North Burma; France; Western Pacific; Warsaw. Insets: Palau Islands; Morotai. Back:"Mindanao, Philippine Islands." Two different oblique views of the island. The large image shows it as seen from the southwest.
Exposures exceeding tolerance: This letter was written in 1944 and applies to the amount of radiation a person could be subjected to under emergency, wartime conditions. Mr. Stone recommends to Dr. Norwood that no man should be ordered to expose himself to more than a tolerance dose (0.1r in a 24 hr period) except in the case of an extreme emergency in which time is of the essence. And that before any man is asked to exceed tolerance that a radiation trained physician be called in for consultation. His recommendations to said physician are that: (a) a single exposure of 1r would cause no harm and could be repeated at long intervals, (b) an exposure of 5 to 10r would produce loss of appetite and nausea and would increase the chances of genetic change but would cause no clinically detectable changes after the incident, (C) an exposure of 25r would do the same as (b) but with greater probability -- he would be personally willing to take a 25r exposure to accomplish an extremely important job, (4) in general keep exposures well below tolerance, (5) due to the genetic effects, women of childbearing age and younger men should be subjected to none and lesser amounts of radiation, respectively.
SUGGESTIONS FOR A HIGH TEMPERATURE PEBBLE PILE: No Description Available.
Newsmap. For the Armed Forces. 276th week of the war, 158th week of U.S. participation: Front: Text describes action on various war fronts: 600-mile water jump, Pacific war in the air, Nazis stage offensive, Budapest Under Siege, Eighth Takes Strongpoint. Maps: Mindoro -- Pacific war in the air -- Red Army -- Western action. Inset maps: Philippine Islands -- Budapest. Back: Map of South Burma and Thailand
ATTEMPTS TO PREPARE TRIFLUOROACETIC ACID BY THE REACTION OF COBALTIC FLUORIDES WITH ACETIC ANHYDRIDE AND ACETONITRILE: No Description Available.
Newsmap. For the Armed Forces. V-E Day + 7 weeks, 184th week of U.S. participation in the war: Front: Text describes action on various fronts and is keyed to map. Photographs: Japanese soldiers, Japanese submarine, Suicide planes, Japanese war industry, aerial view of damage to Tokyo. Map: East Asia and Pacific. Inset maps: 5480 tons of bombs a day! Back: World map with shaded areas showing liberated areas since 7 Dec 1941, enemy held areas as of 8 May 1945; dotted lines show battlelines as of 7 Dec 1941, 1942, 1943, 1944 and 8 May 1945.
Unit purging: No Description Available.
Developments in the Casting Department of the Metal Production Plant at Iowa State College. Special Report on the Casting of Uranium at Iowa State College: This report addresses the casting of uranium rods at iowa state college.
Direct Conversion of the TF₆ to TCl₄: The following report provides a general summary of some methods that could be used to convert hexafluoride into tetrafluoride, but is mainly devoted to the work done on the conversion of tetrafluoride to tetrachloride.
Suspected leak in 107-F basin: No Description Available.
Determination of Tuballoy Uranium With the X-Ray Spectrograph. Summary Report: No Description Available.
Studies of Porphyrin Metabolism, 3. The Relation of Erythropoiesis to the Excretion of Coproporphyrin by Dogs and Rabbits, and to the Concentration of Coproporphyrin and Protoporphyrin in Rabbit Erythrocytes: Report discussing studies regarding porphyrin excretion and hemoglobin metabolism in animals with phenylhydrazine anemia, and studies regarding the coproporphyrin and protoporphyrin in the red blood cells of rabbits.
100 Areas, January 15 through January 21: This report gives the weekly progress for the B, D, and F piles. The report also gives a brief discussion of the following activities: process water control and pressure drop studies; purging of D, B, and F piles; slug corrosion studies; tube corrosion studies; thimble corrosion studies; and graphite expansion studies.
300 Area, January 15--January 21: This report from the reactor fuel manufacturing facilities at Hanford highlights extrusion, canning, and welding operations. Processing of thorium and bismuth is discussed. Radiography of fuels revealed voids that conformed underweight reject measurements.

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