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Iron rust is caused by electrolytic action between the various constituents of iron or steel in the presence of moisture and impurities. It is a continuous process; a coating of rust does not protect the metal underneath. The principal requirements of a rust-prevention process as applied to automobiles, aircraft and other machined and hardened parts are that it (1) Prevent rusting under normal use (2) Prevent the spreading of rust (3) Make no change in dimensions or fits (4) Make no alterations in physical properties (5) Be permanent for the life of the part (6) Be easy and quick of application (7) Be commercially practicable as to cost Of the most familiar rust-proofing processes, the cold, the hot and the high-temperature, the last is eliminated by requirements (3) and (4), while the cold processes and also japanning are eliminated by (2), (3) and (5). There remain three hot processes, the Parker, the Coslett and the Guerini.

Efficiency, appearance and comfort will be the catchwords of the car of the future. Extreme simplicity of chassis will be needed to reduce weight and permit the use of substantial sheet-metal fenders, mud-guards and bodies. The center of gravity should be as low as possible consistent with good appearance. For comfort the width and angle of seats will be studied more carefully and the doors will be wider. A new type of spring suspension is coming to the fore, known as the three-point cantilever. Cars adopting it will have a certain wheelbase and a longer spring base. A car equipped with this new mechanism has been driven at 60 m.p.h. in safety and comfort without the use of shock absorbers or snubbers. It is the opinion of the author that this new spring suspension will revolutionize passenger-car construction.

Progress toward a single standard type of car is not being made. Many different styles will continue to be needed to satisfy requirements of taste, ability, power and speed. Open cars, the backbone of production in the early days, are less in demand. Enclosed cars are already to be had in practically every grade. While there is a trend toward lighter weight the demand for increased luxury and greater safety makes it seemingly impossible to reduce weight in either equipment or body. Just what the result of this conflict of ideas is to be is not easy to predict. The author foresees considerable improvement in design and workmanship, a gain in economy of fuel, greater use of oil in lubricating chassis parts besides the engine, increased durability and fewer objectionable noises.

The factors included in the commercial airplane problem are the practical use that can be made of airplanes, the volume of business that can be expected, the necessary changes from present military types to make an efficient commercial airplane and what the future holds for this new means of transportation. The requirements for passenger transportation, airmail and general express service, are first discussed in detail, consideration then being given to other possibilities such as aerial photography and map-making, the aerial transportation of mineral ores, sport and miscellaneous usage. Changes in the present equipment of engines and airplanes to make them suitable for commercial use are outlined, and special features of aerial navigation, landing fields and legal questions are mentioned.

Airships were not generally considered important before the war. Many thought they would never become practical as a means of transportation. The proper conception of what an airship is having first been explained, the three principal ways in which progress has been made are specified as weight-saving, improvement of overall propulsion efficiency and decreasing resistance and increase in size. The last mentioned feature is discussed in some detail, the conclusion being that practically anything is possible, given an airship of sufficient size. The future needs of airship development are then considered, such as more suitable engines, multiple powerplants, dependability, the development of better fabric and better landing and hangar facilities.

THE author presents a brief description of the design of some of the principal vehicles used in motorizing the artillery, as developed by the Ordnance Department. A few of the vehicles are described, including gun mounts that were being developed at the time of the signing of the armistice. The relative merits of the different types of equipment are discussed.

THE production of gasoline in this country could be increased through the following changes in refinery practice: (1) Universal adoption of a high “end-point,” or upper volatility limit for gasoline (2) General use of more efficient distillation methods and equipment (3) Recovery of gasoline now lost in refinery operation (4) Wider use of cracking processes Other possible methods of increase are not considered of sufficient importance to merit discussion in this connection. Some of the details of the four methods of increase are discussed and it is estimated on the basis of the evidence now at hand that the maximum percentage increases in production under the four heads listed are as follows: (1) 15 to 20 per cent; (2) 10 per cent; (3) 10 per cent, and (4) 100 per cent.

ENGINEERS have different ideas regarding highly efficient and moderately efficient engines, but designers dare not ignore the fact that the public requires today a small very high-speed engine, with good torque at low speeds, and capable of revolving efficiently at very high speeds. These two characteristics are difficult to attain, since in practice one is really opposed to the other. To obtain high speeds with power, the valve areas, valve parts, carbureter, etc., should not be restricted in any way, while to get a good mixture at low speed with heavy torque means a different valve-setting and more or less restricted port and valve areas, etc., to secure high gas velocities. The author states that the fundamentals of high-speed engines are high volumetric efficiency; high compression, to aid in obtaining rapid combustion at high speeds, and light reciprocating and rotating parts, to secure high mechanical efficiency.

THE impression that recent aircraft experience should have taught engineers how to revolutionize automobile construction and performance, is not warranted by the facts involved. Aircraft and automobiles both embody powerplants, transmission mechanisms, running gear, bodies and controls, but their functions are entirely different. The controls of an airplane, except in work on the ground, act upon a gas, whereas with an automobile the resistant medium is a relatively solid surface. Similarly, the prime function of the fuselage is strength, weight considerations resulting in paying scant attention to comfort and convenience, which are the first requirements of an automobile body. Aircraft running-gear is designed for landing on special fields, and is not in use the major portion of the time. The running-gear is the backbone of an automobile, in use continuously for support, propulsion and steering; hence its utterly different design.

The authors advance for discussion some important problems in the construction of airplanes for military use in this country. The functions of military airplanes designed for strategical and tactical reconnaissance, control of artillery fire and for pursuit are outlined. Problems in construction with reference to the two-propeller system, methods of reducing vibration, application of starting motors, details of the gasoline supply-system, metal construction for airplanes, flexible piping, desirable characteristics of mufflers, shock absorbers, landing gear, fire safety-devices, control of cooling-water temperature, variable camber wings, variable pitch propellers and propeller stresses, are all given consideration. The paper is concluded with suggestions for improvement in design relating to the use of bearing shims, the rigidity of crankcase castings, interchangeability of parts and better detail construction in the oiling, ignition, fuel supply and cooling systems.

Starting with the statement that command of the air in warfare rests largely with the side that produces the best single-seater fighter, the author proceeds to outline some of the problems confronting the designer of fighting airplanes, and particularly the smaller ones. Considering better performance and better fighting qualities as the main desiderata, the author discusses means of obtaining them by: (1) increasing the horsepower-weight ratio; (2) decreasing the wing or structure resistances; (3) devising a new arrangement of the supporting planes, with regard to the position of pilot or crew, or by a combination of the above. Considerable space is devoted to methods of decreasing wing resistance, principally by employing low-resistance aerofoils, and the shaping of wing tips is also referred to.

The author states that the purpose of the paper is to outline that phase of metallurgical work pertaining to the connection between the laboratory and production in the automotive industry. Reasons are cited for selecting certain designs for parts to facilitate machining, complete or partial case-hardening, finishing and assembling. The next step is the choice of materials, a subject which is treated at some length. The author then takes up in turn the field for standardization in steel specifications, inspection of materials, physical testing of steels, uniformity of composition of metals, heat-treating operations, methods of carburizing, depths of case-hardening, treatment after carburization, errors in overspeeding hardening operations and drawing heat-treatment at low temperatures. Types of pyrometers, operations on hardened work, inspection for hardness and selection of hardening equipment are some of the other topics discussed.

The efficiency of the automobile engine, as operated on the Otto cycle, is thought by the author to be too low, and he therefore suggests a method of improving it. He considers the various losses by which heat is dissipated in internal-combustion engines and finds that the best opportunity for increasing thermal efficiency is by an increased expansion of the charge. The author suggests that this expansion be carried 50 per cent further than is ordinarily done. In order to obtain higher efficiency at part load, the suggestion is made that instead of throttling the mixture, the admission valves be closed earlier. In case the expansion is 50 per cent longer than the induction stroke and the cut-off takes place earlier as the load becomes lighter, it will be necessary to vary the fuel opening inversely with the air induced. It is suggested that the fuel valve and cut-off lever be connected together and operated by the accelerator pedal or hand lever on the steering wheel.

After a brief consideration of airplane-engine practice in France, England and Germany, the author outlines the problems encountered in designing a twelve-cylinder aviation engine. He explains at some length the difficulties in determining the connection between propeller and engine and shows why valve-in-head location was chosen. Such features of engine design as the mounting of carbureter and exhaust pipes, methods of fuel and lubricant supply and details involved in selecting the lighting, starting and ignition equipment are considered.