From General Statement Purpose of the Report: "The present investigation was undertaken for the purpose of supplying some of the material so badly needed in the valuation and more efficient operation of oil properties. Because of the lack of time for further studies, the amount of data already accumulated and the policy of the Bureau of Mines of publishing as soon as possible any information that may be of use to an industry, the bulletin is issued now."

From General Statement: "Beginning with an investigation to develop the best type of gas mask, the scope of the work extended until it included researches relating to a wide range of devices, such as different types of poisonous and irritating gases and smokes, smoke screens, gas shells and gas bombs, signal lights, and incendiary bombs. When the results obtained through this research were to be applied by the War Department, the Director of the Bureau of Mines cooperated in the selection of men to have charge of manufacture or further development, recommending chemists who subsequently received commissions in the Army. Perhaps the greatest result of the research work has been the demonstration of the value of the services that the chemist and chemical engineer can render in time of need and the recognition of chemical investigations as a necessary function of the Government."

Bulletin issued by the U.S. Bureau of Mines: "This publication is devoted exclusively to a review and abstracts of decisions based on the laws governing the rights and duties of mine owners, operators, miners, and persons trafficking in all kinds of mining properties. It includes abstracts of current decisions of all the Federal and State courts of last resort on questions relating to the mining industries" (Bulletin 61, p. 9).

From Introduction: " This bibliography follows the same general scheme as the bibliography of petroleum and allied substances for 1915. References to articles in these journals have been taken from such sources as were available and credit has been given to those sources. American and foreign patents have been entered by title, without abstracts. A few minor changes have been made in the scheme of classification, which is, on the whole, the same is given in the 1915 bibliography."

From Introduction: "The bulletin aims to give the localities of the various mining districts, and the nature of the present operations and those that have been carried out in the past."

From Introduction: "Vocalization in retorts has been, until recently, the only commercial process of producing spelter, hence the zinc mine operators have had to meet the terms of the zinc mine operators have had to meet the terms of the zinc smelters in regard to the following requirements: (1) Minimum percentage of zinc the ore must contain; (2) the chemical combination of the zinc in the ore; (3) the proportion present of those elements that interfere with the successful recovery of the zinc when the ore is retorted. As stated previously, and as will be shown later, a large part of the valuable mineral content of the ore is lost in effecting this concentration. As a result of the other requirements that have to be met in zinc smelting, much zinc is lost in the mining and milling of zinc ore."

Report discussing Illinois mining statutes.

Bulletin issued by the U.S. Bureau of Mines: "This publication is devoted exclusively to a review and abstracts of decisions based on the laws governing the rights and duties of mine owners, operators, miners, and persons trafficking in all kinds of mining properties. It includes abstracts of current decisions of all the Federal and State courts of last resort on questions relating to the mining industries" (Bulletin 61, p. 9).

From Introduction: "This report gives the results of a study conducted by the Bureau of Mines for the purpose of informing the petroleum industry on the recent progress in the development and application of the absorption process for recovering gasoline from natural gas."

From Introduction: "The purpose of this bulletin is to describe the methods of constructing and operating representative types in the United States used for removing the light hydrocarbons from petroleum by continuous distillation, such plants being commonly known in the trade as topping or skimming plants."

From Introduction: "This report on the electrodeposition of gold and silver from cyanide solutions represents work that has occupied my time at intervals during the past 20 years, The investigations has been carried on simultaneously with my duties as professor of mining and metallurgy of the University of California."

From Introduction: "The report presents statistical data compiled from various sources, showing the production of gold in the United States and other countries, with comparative figures for coal, iron, and other mineral products, and describes the sources and distribution of gold output in the United States."

Report presenting the Miner's Safety and Health Almanac, which contains a calendar and information on diseases that may affect miners and their families. Some more common causes of accidents in mines and show how the miner can lessen the risks of their work.

Report details some examples of dopes and doping on airplanes and balloons and the various properties of different materials. Topics covered include cellulose nitrate dopes, cellulose acetate dopes, dope covers, application of dopes, and fireproof dopes

The aerodynamical constants of an airplane necessary for the discussion of stability are partly observed and partly calculated. Among the calculated coefficients is n(p), which is the variation of yawing moment due to rolling. (author).

Report presents a theory which gives a complete picture and an exact quantitative analysis of the whole phenomenon of the working of blade screws, but also unites in a continuous whole the entire scale of states of work conceivable for a blade screw. Chapter 1 is devoted to the establishment of the system of fundamental equations relating to the blade screw. Chapter 2 contains the general discussion of the 16 states of work which may establish themselves for a blade screw. Chapter 3 is devoted to the study of the propulsive screw or propeller.

This report is a continuation of NACA Technical Report 14. It presents the results of an experimental investigation on the performance of air propellers which was divided into five parts, as follows: (1) Tests under conditions of flight on 16 model propellers of different forms, sections, or pitch ratios from those of Technical Report 14; (2) Tests under conditions of flight on one model propeller of variable pitch; (3) Tests under conditions of flight on three sets of right and left hand model propellers in series; (4) Tests on 12 model propellers to determine brake effect or negative thrust at negative slip; (5) Standing thrust and power tests of 67 model propellers.

Certain parts of an airplane are subjected not only to the stresses imposed by the aerodynamic or flying load, but also to the initial stresses, caused by the tension in the stay and drift wires. Report describes a tensiometer that measures such stresses which is simple in construction, accurate, and easily and quickly operated even by inexperienced persons. Two sizes of the instrument are available. One is suitable for wires up to one-fourth inch in diameter and the other for wires from one-fourth to three-eights inch in diameter.

Among other factors which affect the horsepower of an airplane engine are the atmospheric pressure, and consequently the altitude at which the engine is working, and the compression ratio, or cylinder volume divided by clearance volume. The tests upon which this report is based were selected from a large number of runs made during the intercomparison of various gasolines to determine the variation of horsepower with altitude at three different compression ratios. The test results and conclusions are presented in this report.

Report presents the results of an extensive experimental investigation of the performance of different types of carburetors as effecting the maintenance under all conditions of correct ratio between the weights of fuel and air. It also gives a description of the Bureau of Standards carburetor test plant, test equipment and measuring instruments used to determine the metering characteristics of carburetors.

The purpose of this report is to give a simple treatment of the problem of calculating the final or limiting velocity of an object falling in vertical motion under gravity in a resisting medium. The equations of motion are easily set up and integrated when the density of the medium is constant and the resistance varies as the square of the velocity. The results show that the fundamental characteristics of the vertical motion under gravity in a resisting medium is the approach to a terminal or limiting velocity, whether the initial downward velocity is less or greater than the limiting velocity. This method can be used to calculate the terminal velocity of a bomb trajectory.

Report discusses the theory of energy losses in wind tunnels, the application of the Drzewiecki theory of propeller design to wind tunnel propellers, and the efficiency and steadiness of flow in model tunnels of various types.

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.

"Brass has often been assumed superior to steel for spark plug shells because of its greater heat conductivity. The measurements described in this report prove the contrary, showing that the interior of a spark plug having a brass shell is from 50 degrees to 150 degrees c. (90 degrees to 270 degrees f.) hotter than that of a similar steel plug. It is to be concluded that steel is to be preferred to brass for spark plug shells. This report embodies the results of measurements taken of electrodes and a comparison of brass and steel insulators of spark plugs while they were in actual operation" (p. 5).