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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.

The author discusses the different types of material used in the production of the Liberty engine, the physical properties of the finished parts and the heat-treatments used in making them, applying the information as set forth to the automobile, truck and tractor industries. Under their several heads the different engine pans are discussed with close attention to details. Chemical analyses are given for each part and approved heat-treating temperatures are indicated. Quenching, direct and indirect, water and oil cooling, hard spots, warpage, scaling and hair-line seams are treated. The advantages and disadvantages of the Izod impact test are stated briefly.

Few points have aroused such discussion among users and engineers as that of the desirable number of cylinders in an engine. A large part of the work of the author has been in the direction of attaining the same ends as those achieved by the multi-cylinder engine but by different means. He discusses the relations between torque at clutch and number of cylinders and multicylinder engines and uniform torque, the factors governing torque recoil, torque recoil as a function of car weight and engine balance. His conclusion is that the multi-cylinder engine now so widely used exceeds the real requirements and obtains its smoothness of operation at the expense of more desirable qualities. A reduction in car weight would in his opinion enable existing standards of performance to be maintained and even improved by the use of four cylinders for the heavier type, with all that this means in tremendous advantages to the automotive industry and to the user.

A new type of automotive engine should be the quest of all designing engineers. Investigation has revealed the fact that 68 per cent of all tractor engine troubles occur in magnetos, spark-plugs and carbureters, the accessories of the present-day automotive engine. Four-fifths of the fuel energy supplied is regularly wasted, yet the fuel is a liquid meeting severe requirements of volatility, etc., and is already becoming scarce and costly. In an airplane, fuel is carried by engine power. In ocean-going cargo vessels it increases available revenue space. It is at once clear that for purely practical reasons the question of fuel economy, no less than the question of the nature of the fuel, becomes momentous. What fuel will do is entirely a question of what process it is put through in the engine; in what way combustion is turned into power.

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.

The limit of acceleration has been reached. What may well be considered a maximum for practical service has been secured. The present seven-passenger body is as roomy as could be desired. There should be no need for further increase in size. The author believes the total weight of this large car will be reduced to between 3500 to 4000 lb. To make this reduction without sacrifice of durability greater use must be made of alloy steels and aluminum alloys. The tendency in body design and style is toward smoother lines, fewer breaks and a more graceful contour. The number of closed cars is increasing. There will be a general simplification of detail throughout, better wiring, better lubrication, an increased use of oilless bushings and fewer grease-cups. Brakes and wearing parts will be made more accessible and easier of adjustment. The take-up points for the various adjustments will be placed so that they can be reached with ease.

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.

After noting that the early development of the automobile industry took place at a time when gasoline was a drug on the market, this paper reviews the cycle of operations of a standard gasoline engine in order to point out its limitations and the possibilities of utilizing a less volatile fuel than gasoline and of securing lower consumptions of fuels of all kinds. Compression and expansion limitations and the reduction of mean effective pressures at light loads are considered. Disadvantages of throttling control are pointed out, citing as a parallel example the trend of steam engine design away from this means of control. The author then outlines the advantageous features of the improved Diesel engine design, and by means of curves shows the great fuel economy of this type as compared with gasoline engines. He concludes by defining “the ideal tractor engine.”

The author outlines the history of the 550 submarine chasers built for the British Government between April, 1915, and November, 1916, and attributes the success of the undertaking largely to scientific standardization. He cites some of the early difficulties in obtaining supplies and tells how they were met, and mentions how and why the fabrication was carried out in this country and the assembly made in Canada. The paper concludes with citation of the principal dimensions of the boats, power, speed and cruising radius. In the course of the discussion the author refers further to the power plant and mentions some of the war-time duties of this type of craft.

The author first mentions hot-tube ignition, which preceded the spark-plug, then the low-tension type of make-and-break ignition, following with the development of spark-plugs. He compares the conical and petticoat types of porcelain and discusses at some length the insulating materials used in spark-plugs, such as porcelain, mica, steatite, glass and quartz. In this connection he covers the composition of the material, its dielectric strength, carbon-absorbing ability, heat-conductivity, mechanical characteristics, and the difficulties of glazing. Under the heading of general design of spark-plugs the author takes up such points as assembly of insulator and center electrode, electrodes, gaskets, and separable and integral plugs.

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.

This paper contains a brief description of the Entz electric transmission. Wiring connections are given of the several speeds, for electric braking, for starting the engine and for charging the battery. The statement is made that the electric transmission eliminates and does the work of the friction clutch, the clutch pedal, the transmission gears, the flywheel and separate starting and lighting systems.

The question as to whether a part should be made or bought is one that must be settled by the individual maker according to the value of his product, the nature of the part, his capital available for manufacturing purposes and the price at which his product is sold. The author describes the practice followed by some of the large companies, showing that in spite of their being quantity producers, they have found it desirable to buy a number of important parts. Certain parts are rarely made by automobile manufacturers, either because they can be bought more cheaply or because the machinery to produce them is intricate. The author sums up the problem by stating that a manufacturer makes the unit on account of not getting deliveries or because he does not get a fair price from the parts maker or an article good enough to satisfy his conditions. In order to give individuality to the product, the car maker often produces certain parts, such as the engine, himself.

The author limits his consideration of rear axles to that of the bevel-gear type and takes up the subject under the heads of load-carrying member, gearing, driving-shaft, brakes and materials. Several different forms of cast and pressed axle housings are briefly described. Mention is then made of the axle gearing and data given showing the end thrust for straight-tooth bevel pinions. The methods of supporting pinions and of attaching bevel gears to the differential are discussed. Forms of differentials are considered, several different conventional types being illustrated. The subject of driving shafts is briefly reviewed, as is also that of brakes and brake materials. The author concludes his paper by figures showing the tensile strength, elastic limit and elongation of the metals used in the various parts of the rear axle and also explains some oil-retaining and dust-protecting features of design.

The author has selected fourteen automobiles on which to make a study of the factors of safety used in their design. He considers specifically the front axles, front-wheel spindles, propeller-shafts, clutch-shafts, transmission drive-shafts and rear-axle drive-shafts. The method of calculating the stresses is outlined; compositions of the steels used are given; and complete data are presented showing the factors of safety of the various parts, together with the intermediate figures used in obtaining the factors.