"The behavior of a liquid or gaseous medium, in which a solid body can move freely under the action of a force of constant magnitude and direction, is yet little known. Only in connection with a few special problems, which belong in this field, have experiments been tried and these chiefly concern technically important cases. The behavior of the simplest shaped bodies has as yet been scarcely investigated at all" (p. 1).

The contest for engines of great endurance had entries of 13 types by the following firms: Breguet, Farman, Fiat, Hispano-Suiza, Lorraine-Dietrich, Panhard-Levassor, Peugeot, Renault, and Salmson.

Hitherto, definite specifications have always been made for fuel oils and they have been classified as more or less good or non-utilizable. The present aim, however, is to build Diesel engines capable of using even the poorest liquid fuels and especially the waste products of the oil industry, without special chemical or physical preparation.

"The recent development of technical science demands maximum reliability of functioning, together with maximum utilization of construction materials. For this purpose we must know what stresses are produced during functioning. One cause of great stresses are mechanical vibrations and this report describes a method of using an oscilloscope to measure the stresses of rapidly changing phenomena" (p. 1).

The use of exit cones and different blade configurations to reduce the motive power required in wind tunnels is discussed in this report.

The theory (wing experiments in an artificial air stream are subject to error, due to the fact that the wing is not situated in an unlimited body of air) by means of which the given drag correction was obtained, was based on various assumptions (e.g., elliptical distribution of lift) which do not always hold true. For this reason it was desirable to test the equation for the additional drag in regard to its reliability and range of application.

Report issued by the U.S. Bureau of Mines on experiments conducted to improve the cab conditions of freight engines. The temperature, gas content, and other properties are presented. This report includes tables, graphs, and illustrations.

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"The development of aeronautic instruments. Vibrations, rapid changes of the conditions of flight and of atmospheric conditions, influence of the air stream all call for particular design and construction of the individual instruments. This is shown by certain examples of individual instruments and of various classes of instruments for measuring pressure, change of altitude, temperature, velocity, inclination and turning or combinations of these" (p. 1).

"If the low-powered airplane is to be used advantageously by private individuals, the most important consideration is a smaller fuel consumption and, hence, a lower engine power. From experiments with gliders, it appears entirely possible, by utilizing ascending winds (on the weather side of mountains and those generated by the heat of the sun) and by employing engine flight intermittently, as required to fly long distances over land" (p. 1).

Memorandum describing a device, constructed according to the system of Gati, with which it is possible to measure the sound of an engine and test the effect of a silencer.

The theory, structure and working of a vector slide rule is presented in this report. This instrument is used for determining a vector in magnitude and position when given its components and its moment about a point in their plane.

The following paper is based on the results of tests, upon duralumin columns, contained in two theses presented to the Department of Civil and Sanitary Engineering of the Massachusetts Institute of Technology.

Engine conditions such as pressure characteristics, temperatures, and mechanical fatigue enable the employment of a criterion of general fatigue which simultaneously takes account of both mechanical and thermal conditions, for the sake of comparing any projected engine with engines of the same type already in use.

The following experiments on the air flow behind bodies were made for the purpose of assisting in the explanation of the phenomena connected with air resistance. The first two series of experiments dealt with the phenomena behind a cylinder. The third series of experiments was carried out behind a streamlined strut.

This paper relates some of the problems commercial aircraft companies have in attracting larger numbers of paying customers. The author discusses some remedies such as changing the public perception of flying as dangerous.

"It is obviously interesting to know the names of those who were the first contributors to aeronautical science. Therefore, without claiming to give a complete history, I present in this article a summary list of names in chronological order relating to the history of experiments on the resistance of the air and its application to aeronautics" (p. 1).

The construction of the Magnan glider, M-2, is presented which is designed to fly in so-called horizontal winds. Details of the wings, fuselage, tail surfaces, controls, landing gear, characteristics, operation, photographs, and drawings are provided.

"These notes are intended to furnish practical and general data on the effect of altitude on engine power. The effective horsepower of an engine is a function of the mean pressure of the fluid acting on the pistons, of the R.P.M. of the engine and of the mechanical efficiency" (p. 1).

This article presents the difficulties and triumphs of the airship Dixmude in its long distance flight over North Africa as described by one of the occupants.

In experimenting with airfoil models in a wind tunnel, the magnitude of the forces acting on the model is affected by the fact that the air stream in which the model is suspended, has a restricted cross-section. In order to utilize the results for an airplane in an unlimited quantity of air, a correction must be made. The magnitude of this correction was determined by Prandtl by the application of his wing theory.

Report presenting the development in air transport that has taken place since civil aviation between England and Europe started at the end of August 1919. The primary subjects explored include the character of loads on aircraft, routes operated, results in passengers carried and efficiency of the service, costs of the service, question of subsidies, and probable future developments.

The present report treats the subject of testing small models in a wind tunnel and of the methods employed for rendering the results constant, accurate and comparable with one another. Detailed experimental results are given.

Experiments were made on the resistance of four airplane wheels of different sizes and coverings and two Lamblin radiators. The results show the important influence of the wheel coverings. The closing of a shutter, which was fitted to one of the radiators, considerably lessened the resistance.