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The author presents the practical side of the body designer's work and refers to him as being between the office and the shop, the one who stands in the way of the impatient man that wants action without preparation. The development of the body designer and body designing is reviewed and the position and duties of the designer are stated at some length. The design factors are considered in detail and the making and utilization of wax models are described, followed by a lengthy consideration of curved-surface bodies, wood body frames, style and body types. The fittings and minor design details are discussed and future designs predicted from present indications. The author explains the body designing business in detail to refute the suspicion that the working methods of body designers are different from those employed by the other members of an engineering force because body designing is different and distinct from the other branches of motor-car engineering work.

Vibrations of several kinds can occur in crankshafts, but the principal ones are transverse and torsional; the paper deals entirely with the latter. A simple case of torsional vibration is considered first and the principles are applied to the torsional vibration of a shaft, the argument being carried forward at some length. A discussion of critical speeds follows and this is supplemented by a lengthy mathematical analysis, inclusive of diagrams. Calculations were made to determine the period of the shafting of United States submarines S4 to S13 and these are described. The three cases investigated include the charging condition when the engine is driving the dynamo, the after clutch being disconnected; the surface condition, when the engine drives the propeller; and the submerged condition, when the motors drive the propeller, the forward clutch being disconnected. Calculations were made also with a Sperry magnetic clutch substituted for the usual flywheel and clutch.

The early wheels merely rolled, carried weight and resisted side strains; later they were called upon to transmit braking forces and still later the driving force. Prior to the automobile, wire wheels were not called upon to support much weight and the usual type was that used for bicycles. When automobiles were first built, bicycle-type wire-wheels were employed and used until the demand for larger wheels presented unsurmountable obstacles. From that time a development was in progress in this country and in England that resulted in the triple-spoke wire-wheel which has grown in popularity since 1912. The different types of wheels are discussed and the advantages and disadvantages of wire wheels stated; three diagrams are shown. As the wire wheel is a “suspension” wheel, the car weight is hung or “cradled” from scores of resilient, flexible spokes, and the pull is always on three-quarters of the spokes.

The paper surveys the economic and engineering aspects of the automotive industry, so that engineers can align themselves with its future development. Better performance and longer life due to improved design and materials distinguish the 1920 car from its predecessors. One of the healthiest signs in the industry is the uniform determination of practically every manufacturer to improve the quality of his product. The designer has been forced to extend himself in getting the highest possible output from the smallest possible units. This trend is very noticeable. Conditions relating to prices, the return to peace-time production, the potential demand for cars and the present supply, and the probable improvements in cars are then reviewed, the thought then passing to a somewhat detailed discussion of detachable-head engines.

For many years plywood has been used for such automobile parts as roofs and dash and instrument-boards, but it was not until the closing of the European war that the extent to which this material was used in automobile construction greatly increased. The sudden requirement of airplanes created a large demand for plywood which would withstand the severest weather conditions. Glues were perfected that enabled plywood to withstand 8 hr. of boiling or 10 days of soaking in water without separation of the plies. Plywood as an engineering material is discussed. It is then compared in considerable detail with ordinary boards and also with metals and pulp boards, statistics and illustrations being given. The molding of plywood is considered with especial reference to employing plywood for surfaces having compound curvatures, and the limiting factors in the use of plywood for this purpose are mentioned.

The only direction in which flexibility of an organization can be considered is that of successful progress. Flexibility uncontrolled is liable to lead to retrogression instead of progression. During the war, every available unit of man-power was called into use, and all specialized intelligence was stretched almost to the breaking point. This was particularly true of the intelligence in the automotive industry. Demands were made in connection with the airplane, tanks, agricultural tractor and submarine chasers, as well as the more stabilized automobile and trucks. The most skilful men naturally gravitated to the most difficult work, in the problems surrounding the airplane and the tank, and, while in general there were not nearly enough men, the scarcity of skill was more noticeable in the older branches of the industry. It was there that the necessity for a flexible organization demonstrated itself. The first necessity was a rigid base from which progress could be made.

Continued lowering in the grade of fuel obtainable compels automotive engineers to produce engines that will utilize it with maximum economy. The manufacture of Pacific coast engine-distillate with an initial-distillation point of about 240 and an end-point of 480 deg. fahr. was abandoned by the principal oil companies early in 1920. Utilizing this fuel efficiently through its period of declining values forced advance solution of some fuel problems prior to a general lowering of grade of all automotive fuels.

Since the Fifth Avenue Coach Co. of New York is the largest successful company operating motor-buses in this country, the author gives a rather comprehensive description of this company's systems and methods, stating the three main divisions as being the engineering, mechanical and transportation departments, and presenting an organization chart. Departments concerned with finance, auditing, purchasing, publicity, claims and the like, which follow conventional lines, are not considered. The engineering, research, mechanical, repair and operating departments are then described in considerable detail. Six specific duties and responsibilities of the research department are stated and six divisions of the general procedure in carrying out overhauls for the operating department are enumerated. Regarding fuel economy, high gasoline averages from the company's standpoint mean economy, well-designed and maintained equipment, and skilled and contented operatives.

MEXICO achieved second place among the petroleum-producing nations of the world in 1918. This position will not soon be relinquished, judging from the study made by the author of the two general regions from which petroleum has thus far come. The Petroleum Commission of the Mexican Government has issued statistics covering the production by years since the industry started. It is confidently hoped that future production will continue, as indicated, to stop the gap, constantly increasing and critical, between production and consumption in the United States. A section of the paper is devoted to the export trade, especially with this country, which furnishes the nearest great market.

THE automotive industry is developing without due regard to the fuel situation. This situation is an integral part of the automotive field and should not be left out of account. Owing to the pressure of automotive demand, the supply of engine fuel is changing in character and price, with danger of precipitant alterations; there arises in consequence a fuel problem which cannot be adequately solved without the active participation of the automotive industry.

THE Navy Department established the Naval Aircraft Factory (a) to assure a part, at least, of its aircraft supply; (b) to obtain cost data for the Department's guidance in dealing with private manufacturers, and (c) to have under its own control a factory capable of producing experimental work. The history of this development is given in some detail, including statistics of size, valuations and output.

SOME practical examples of correct as well as of incorrect methods of designing are studied, using a motor vehicle for illustration. The mechanism of such a vehicle should be very simple, and the elimination of certain links and members here and there may become more or less desirable. It is essential to know how much this will burden other members, and what strengthening or even redesigning may become necessary. It has been proposed to eliminate the torque and radius-rods. By formulas and drawings the author shows how complex the problem is and the various changes that must follow such an attempt. A vehicle must have much stiffer springs if the torque rod is to be eliminated. This inevitably leads to a study of springs and of the influences of brakes. A vehicle can be operated at somewhat higher speed with a torque-rod.

EVERY plow in use should have 10 b.-hp. available. Every tractor engine should deliver continuously at least 33 hp. If the 330-cu. in. engine mentioned were as good as a Liberty airplane engine, it could deliver 57 hp. at 1000 r.p.m. The horsepower actually obtained is as follows: 41.5 in the laboratory 33.0 at the factory 29.0 when burning gasoline 23.0 when burning kerosene 21.0 with poor piston-rings 19.0 with poor spark-plugs 9.5 available at the drawbar The great engineering problem of the future lies between the 57 and the 23 hp. From 19 to 9.5 hp. is the manufacturer's problem. The main difficulties, as outlined by the figures given, lie in the combustion chamber and its ability to dissipate the surplus heat, and in the limitations of fuel. There will be no need for refiners to continue to break up the heavier fuels by processes already so successful, if by ingenuity and good understanding of thermodynamics these can be made to burn in present-day engines.

BUREAU of Mines refinery statistics for the calendar year 1918 show a production of different types of petroleum fuel products represented by the following approximate figures: Added to this are 3,100,000,000 gal. of crude oil, used as fuel without refining. The statistics do not distinguish the different classes of fuel oils, and the following provisional estimate has been made: Processing or refining costs for the different oils are difficult to estimate and of little significance in determining the selling price, which is controlled by the law of supply and demand. All types in the last list can be used in so-called heavy-oil engines, but the gas oil and light residuum are most desirable in the order given. They are less plentiful than the heavy-residuum type which generally cannot be used without special equipment for preheating. The proportionate yield of gas oil can be increased if a sufficient demand is developed.

Naval aircraft are distinctively American types. Only one foreign seaplane was copied by the United States during the war, and when finally put into production it resembled the British prototype in externals only. While the Navy does a large part of its own designing and building through a corps of naval constructors, its theory of manufacture is to assemble parts procured from separate makers, and private design and construction are encouraged by contracting with builders. Available talent both in and out of the service and the facilities of parts makers, the new materials developed during the war and organized engineering which drove the entire process toward speedy results were appropriated by the Navy. The NC flying boat is typical of U. S. Navy practice. In the same way the dirigible C-5 is a purely American type. The development of really large flying craft before 1917 was held back because no suitable engine had been designed. When the 350-hp.

The engine-fuel situation has changed almost overnight. Oil-consuming activities have taken on an accelerated expansion and the situation has shifted from excess supply to a position where demand is assuming the lead and is seeking a supply. A gasoline stringency, accompanied presumably by a marked rise in price, is a prospect to be anticipated. The production of gasoline is increasing more rapidly than the production of its raw material, crude petroleum. The available supply of the latter is very limited in view of the size of the demand. As a direct result of the situation, gasoline is changing in character and becoming progressively less volatile. The low thermal efficiency of the prevailing type of automotive apparatus contributes strongly to the demand for gasoline as engine fuel and has a bearing upon the quantity and the price of this specialized fuel.

In a rapid and illuminating sketch of the early work done in electricity and magnetism the subtle and close connection between pure research and so-called industrial research is shown. Building on the work of Faraday, Maxwell and Hertz, Marconi, in our day, had the confidence to do the practical thing. From the Hertz oscillating system he passed to grounded antennas at both sending and receiving stations. From the well-understood tuning of electrical circuits and the coherer of Professor Branly he secured increased efficiency and selectivity. Mr. Edison, following the early work of J. J. Thomson at Cambridge University, England, devised the first practical application of the electron apparatus, the Edison relay. The vacuum tube became in the radio field an amplifier, an oscillator and a modulator, the audion. In addition to these interesting developments are the Poulsen arc, the Alexanderson alternator and other alternators of German design.

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.