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obtained by proper use of gravel or rock chips on the asphalt surface. While the present method and equipment are subject to further changes, particularly in regard to tests at constant pressure and possibly lower temperatures, the general procedure appears to be useful for studying directly an important property of asphaltic products and is to paving and roofing asphalts. Since the photooxidizing action must be closely related to the tendency of asphalts to harden in service, a measureIllentof the type described may be useful in determining the ability of an asphalt to retain its initial physical properties.
Fuel and
Oil for
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Literature Cited (1) Abraham, Herbert, “Asphalts and Allied Substances”. 3rd ed. p. 836, New York, D. Van Nostrand Co., 1930. ( 2 ) Anderson, W. T., Jr., and Robinson, F. W., J . Am. Chem. S O C . , 47, 718-25 (1925). ( 3 ) C a n n m M. H.3 and Fenske, M. E., IND.EKG.CHEM.,28, 1035 (1936). (4) Hill, J. B., and Coats, H. B., Ibid., 20, 641-4 (1928). ( 5 ) Marcusson, J., “Die naturliche und kunstlichen Aspilake”, 1931. (6) Strieter, 0. G., and Snoke, H. R., J . Research ~Yntl.Bur. Standards, 16,481-5 (1936). (7) Thurston, R. R., and Knoivles, E . c., IN,,. E ~ G .c H E ~ ~ . 28, , 88 (1936).
Motor Transport
Future Needs T. A. BOYD General Motors Corporation, Detroit, Mich.
HE first need of the future is an adequate supply of fuel T and oil a t low cost. In chemistry lies one of the chief reasons why there has never been a gasoline or oil fam-
regular-price gasoline has been boosted from 60 to 75 and more (Q), and there is every prospect that this upward evolution will continue, as economics and advancing technology permit. It is due to these chemistry-aided developments that a fuel and oil famine has not appeared within the past twenty years, while consumption of gasoline has risen fivefold to the immense volume of 500 million barrels a year, or over 20 billion gallons (Figure 1). There now appears to be little prospect of an early failure of petroleum, and a recent government publication (11) concluded that “discovery will continue to meet our national requirements for a considerable period”. If and when petroleum should fail to be adequate, however, chemistry offers the chief assurance that oil and liquid fuels can be produced from other source materials, such a5 coal, oil
ine in this country, as well as one of the principal assurances that there will not be one. I n respect to petroleum as a continuing source of fuel and oil, chemistry contributes in several ways to assurance for the future. It contributes to discovery techniques by assisting in the various scientific methods of finding where oil is located. Scientific exploration accounted for 98 per cent of the new oil pools discovered in 1938 (6). Chemistry contributes through metallurgy, oil well cementing, and the control of drilling muds to drilling successfully to the deep strata in which much petroleum is found. It contributes through the controlled acid treatment of producing formations, one of the manv technological advances by which the amiunt of petroleum from an bil field has been increased, after i t has been located and drilled; in recent years this has sometimes been by more than twofold (21). Chemistry contributes through cracking, polymerization, alkylation, and similar processes, by means of which the amount of crude oil required to make each gallon of gasoline has been practically cut in half during the past twenty years (8). The savings in petroleum required, as made by these improvements, has amounted since 1920 to one third as much as the total world production of crude oil during all the eighty years since 1859 when “Drake’s folly” turned out to be a n oil well. Chemistry contributes also by making the gasolines produced by these processes in such nearly knock-free forms as to Courteau. Yellow Truck and Coach .bfanu/acturing C o m p a n y permit the use of high-efficiency engines LUBRICATING OILS MUSTMEETSEVERE SERYICE CONDITIONS which make each gallon of gasoline go farther. This Diesel- owered motor coach one of a fleet of twenty-one, operates over one of four The chemical-compound,tetraethyllead, also sections of &e route between C h i k p o and t h e Pacific Coast. The mileage covered b y t h e fleet since delivery in June, 1939, is so large as t o average for each coach nearly 0 . 5 mile per has been of considerable assistance in this minute (26.5 miles per hour), countinq no time out day or night. T h e present schedule ia regard. Since 1930 the octane number of about 22.000 miles per month for each coaoh.
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I N D U S T R I A L A N D E N G I N E E R I N G CHEMISTRY
Chemistry offers the chief assurance that the first need of the future for motor transport, a plentiful supply of oil and liquid fuel, will be met. This assurance comes out of all the chemist and the chemical engineer are doing to help find petroleum, to get the maximum amount of oil from the sand, to refine each barrel of petroleum to best advantage, to utilize fuel and oil efficiently, and to make coal, oil shale, and vegetation available as reserves for the more distant future. In gasoline, both for ground and air vehicles, the principal prospect of a further major improvement appears to be in degree of freedom from knock. Freedom from knock depends upon the chemical constitution of the fuel components. The use of Diesel fuels in automotive vehicles is still too new to point future directions with complete clarity, but the principal improvement will perhaps be in ignition quality. In lubrication some of the major needs are better and more stable lubricants and better means of telling whether an oil is good enough for any given service.
shale, and vegetation. And the guarantee that chemistry seems to offer of a plentiful supply of oil and liquid fuels from these substitute sources, notably coal, appears to be good for a long time in the future. The two most promising processes of making liquid fuels from coal are the hydrogenation of coal (Bergius process) and the hydrogenation of carbon monoxide made from coal (Fisher-Tropsch process). I n 1937 one third of the motor fuel consumed in Germany is understood to have been synthetic gasoline from coal, and smaller amounts of that consumed in Great Britain, France, Japan, and Italy have been made from coal (8,19). I n regard to the adequacy of American coal reserves to meet the demand for gasoline, should that ever be necessary, not more than 2 per cent of the original supply of bituminous coal in this country has yet been exhausted. Fieldner (10) pointed out that the estimated reserves of coal and lignite in the United States are large enough to cover the entire state of Ohio (41,000 square miles) to a depth of 76 feet. “At the 1929 rate of energy consumption, assuming that coal will carry the load after oil, gas, and oil shale are exhausted, and allowing 30 per cent for loss, coal would last 2100 years” (10). Thus it appears that, thanks to the advances in chemistry which have made coal available as a source of motor fuel, an adequate supply of fuel and oil for motor transport is in sight for a long time to come. Substitute fuels from sources other than petroleum, such as coal, oil shale, and vegetation, are more costly than gasoline made from petroleum but not prohibitively so. It has been estimated that, in the present state of the art abroad, gasoline could be produced from coal in this country a t from 14 to 16 cents per gallon (8). But since this is three to four times the present manufacturing cost of gasoline in the United States, coal will not be used here to make gasoline so long as the supply of petroleum proves adequate.
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Making gasoline from coal in this country will have to be preceded by an immense amount of research in chemistry and chemical engineering, as well as by investments on a huge scale. As a praiseworthy safeguard for the future the United States Bureau of Mines has been pioneering for several years in the operation of an experimental coal hydrogenation plant, primarily to determine the suitability of American coals for conversion into liquid products by the hydrogenation process and the conditions under which the maximum yield of oil can be obtained. The results of this research thus far show that with bituminous coals, subbituminous coals, and lignites, from 85 to 95 per cent of the dry ash-free coal substances can be converted to liquid and gaseous products, much of which would make good fuel for motor transport (9, 11, 19).
Motor Gasoline What the requirements of the past have been in respect to amount of gasoline consumed, as well as an estimate of the trend for the two decades following are shown in Figure 1. Included also is a correlative graph of motor vehicles in use during the same period. The estimates for future years up to 1960 were made in 1935 by a committee of the American Petroleum Institute (1). The curve for total motor vehicles in use up to 1939 does not represent registrations as such but is an adjusted value, after Leonard P. Ayres (6), which represents the approximate number of vehicles in actual use a t the end of each year. This figure for current years is less than total registrations by about 2 million.
FIGURE 1. MOTOR VEHICLES IN USEAND GASOLINE CONSUMED
According to these estimates, total motor vehicles in use will increase about 30 per cent during the next 20 years to 37 million, and gasoline consumed will increase 20 per cent to 590 million barrels, or about 25 billion gallons. Whether or not these forecasts made five years ago prove to be accurate, it does seem probable that a smaller proportionate increase in gasoline consumed relative t o motor vehicles in use is justified by the prospect that miles per gallon will be greatly improved in the future. That miles per gallon have not been boosted more rapidly in the past has been due to the demands of car buyers for continually higher and higher performance-greater accelerating capacity and hill-climbing ability. How the performance of cars has been increased in recent years, thanks
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to higher octane numbers, better volatility, and other factors, is shown for six high-production cars in Figure 2. Performance (in terms of brake mean effective pressure times cubic feet displacement per ton mile) has been boosted since 1927 by about 45 per cent on the average. At the same time economy (in terms of ton-miles per gallon) has been improved by an average of more than 20 per cent. 80
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pression. It was such as to give an excess gain in performance above that which could be converted into more miles per gallon without major engineering changes. Figure 4 presents similar data for the same engine with compression boosted still farther to a ratio of 10.3 to 1. The axle ratio was again reduced to give the original level of performance at 20 to 30 miles per hour. At this higher compressionthe fuel required was something above 100 octane number, however. But the gains in miles per gallon were about 70 per cent a t 20 miles per hour, about 65 per cent a t 40 miles, and about 50 per cent a t 60 miles. Here, as before, there was an excess gain in performance a t the higher speeds which was not converted into more miles per gallon. From an altogether knock-free fuel it would not be hard to get either double the power or nearly twice the miles per gallon, but not both a t once. Such a fuel should make possible an engine of much smaller displacement than that of today. If with 100-octane gasoline, miles per gallon could be increased only by 50 per cent, the saving to the car user would amount to half the present retail price of gasoline, or about 9 cents per gallon. Therefore, even if the present cost of manufacture (about 5 cents per gallon) should have t o be doubled to make gasoline of 100 octane number, assuming no change in cost of distribution, a net saving in cost of about 20 per cent would still remain to the car user.
YEARS
FIGURE2. ANCE AND
IXCREASE IN PERFORMECONOMY IN RECENT YEARS
80,
7€
G A I N IN PERFORMANCE
But only an incidental improvement in economy can be obtained when the primary objective is to boost power. Once the demand of car buyers for higher performance has been satisfied, however, it will be possible to utilize further advances altogether in improving miles per gallon. It begins to appear that from now on, the car user may prefer to take the benefits of further improvements in fuels and of advances in engineeringin terms of more miles per gallon. If so, one of the advances that would aid greatly in making higher fuel economies possible would be further increases in the octane number of gasoline or in its degree of freedom from knock.
T
GAIN IN PERFORMANCE
ipI%K: - .‘ MILEI PER HOUR-ROADLOAD
FIGURE 3. GAI~YS WITH
A FUEL OF APPROXIMATELY 100 OCTANENUMBER AS CORIPARED WITH 70
Experimental data on the gains in miles per gallon with gasoline of approximately 100 octane number as compared with one of 70 are shown in Figure 3. The results were obtained by boosting the compression ratio of the engine in a conventional car, as found possible with gasoline of approximately 100 octane number, and then modifying the axle ratio to give the original level of performance at 20 t o 30 miles per hour. At 20 miles per hour the entire gain was thus i n miles per gallon, and it amounted t o about 45 per cent. At higher speeds the gain in miles per gallon was not quite so large. But the lower values there were due in part to the ehape of the power curve of the engine with boosted com-
+
G A I N IN M I L E 5 PER GALLON
LI 20 P
I I”
MILES
ma HOUR-ROAD LOAD
FIGURE4. GAINS WITH A FUELOF MORETHAN100 OCTANENUMBER AS COMPARED WITH 70
There are some problems relating to the use of high-octane fuels in automobile engines, such as more critical tendency to knock from the effects of cylinder carbon and from variations in spark timing. One of the biggest of these problems relates to the large shifts in degree of freedom from knock which high-octane fuels themselves sometimes undergo as engine operating conditions change. This problem exists, to a relatively minor degree, in motor gasolines of the present and is called “sensitivity”. But in the case of fuels with high freedom from knock, the magnitude of the fluctuation with changes in engine operating conditions may, by comparison with present-day gasolines, be extremely large. Thus the higher the octane number, the more important it will be to fit the engine t o the fuel and the fuel to the engine. But if high-octane fuels were available, they could be made to yield some considerable improvement in car miles per gallon, and thus help t o make each barrel of petroleum and each gallon of gasoline go farther. The job is t o produce such fuels a t low cost and to find how to use them to best advantage. These results can be accomplished only by a great deal more pioneering research on just what kinds of hydrocarbons it is best to make, on how to produce them most economically, and on how t o utilize them to best advantage. As to other advances in gasoline for the future, nothing seems to come under the classification of a major need, al-
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though other improvements of advantage will be made. The ideal automobile fuel must have these five major properties: It must be plentiful, cheap, and easy to vaporize, have a high content of energy, and be hock-free. Gasoline as now made from petroleum fills this bill fairly well, except for the requirement of being hock-free. I n respect t o abundance, there has never been a shortage of gasoline in this country, nor, is any in immediate prospect (21). I n respect to cost, gasoline is currently sold at the refinery for about 6 cents a gallon. That is only 1 cent a pound, or somewhat less than the current price of good scrap iron. The maintenance of this cheapness in so far as possible is one of the primary needs of the future. I n respect to ease of vaporization, the gasoline of today is fairly well suited to the needs of motor transport. The volatility of gasoline has been greatly improved in recent years (4). I n the early 1920’s gasoline was so hard t o vaporize that a considerable portion of the papers presented a t meetings of the Society of Automotive Engineers were devoted to various ideas for stoves, hot spots, and other means of a p plying heat to intake manifolds. At the same time, engines were being strangled by the small intake pipes needed to get the wet mixtures into them. But today, owing largely to more volatile gasolines, the automobile engine is able to get its breath much more easily, and the air it breathes does not have to be so hot and stifling. During recent years changes in the volatility of gasolines have not been nearly so great as during the decade from 1920 to 1930 (4),and perhaps nothing considerable in the way of further changes in volatility is a major need. I n energy content, gasoline from petroleum is ideal. It has the highest heat content per pound-about 19,000 B. t. u.-of any known liquid that would be suitable. The man who puts ether or TNT into his gasoline to boost its power, as some drivers of racing cars have been known to do, does not really increase its energy content. He decreases it. It is thus in respect to freedom from knock that the principal prospect of a further major improvement in gasoline lies. And this, involving as i t does the making of hydrocarbons with certain types of chemical structure (16),is
VIEWS IN THE PETROLEUM REFINING OF PENNSYLVANIA STATE LABORATORY COLLEQE Above. Pilot plant equipment for fractional distillation of gasolines and solvent treatment of lubricating oils. Below. Laboratory equipment for the solvent treating of oils.
INDUSTRIAL AND ENGINEERING CHEMISTRY
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A MODERNALKYLATIONPLIST
a job for chemistry and chemical engineering, of great difficulty and immense magnitude. But already through the commercial application of polymerization, hydrogenation, alkylation, isomerization, and other chemical processes, this very thing is being done on a huge scale. “We are so breathless with the progress already made”, said Howard (IC), “that few of us are able to see where this road along which we have moved so rapidly over the last few years will lead us. Apparently it is leading us in the direction of converting the natural hydrocarbons of petroleum into simpler compounds of low molecular weight, and then recombining these simpler compounds in new ways to obtain an entirely new molecule having the characteristics that we want, and which we cannot obtain in the natural molecule.”
Fuels for Aircraft The greatest room for further advances in aviation fuels appears also to be in degree of freedom from knock. It is in aircraft that most can be gained from increases in octane number, and there does not appear to be an important need for major changes in the other essential qualities of gasoline for aircraft. Boosts in octane number are particularly valuable in aviation gasoline because, with suitable changes in power plants, larger pay loads are made possible. It has been estimated ( 3 ) that the earning capacity of some airplanes, such as those in long-distance or transoceanic service, could be increased enough as octane number is boosted to offset a n additional cost of 2 to 8 cents per gallon for each octane number of improvement above 73, if such an increase in cost were necessary. The variation is with type of plane and conditions of operation. Other estimates range from less than 2 to more than 8 cents, depending upon operating conditions (13). It has been concluded, therefore, that for high-octane fuels in aircraft “the indicated increases in earning power are so much greater than any probable cost increases that the upward trend of octane number re-
quirements and use is clearly evident” ( 3 ) . And in military aircraft the highest possible power is wanted for a different reason. The maximum mean effective pressures of aircraft engines using the best commercial fuels of the time have risen from 125 pounds per square inch in 1930 to 200 pounds and more today, when aviation gasolines of 100 octane number are available (4). But mean effective pressures as high as 600 pounds are said to have been obtained in small engines with special noncommercial fuels. It thus seems reasonable to suppose that the need for higher horsepowers per pound in aircraft will stimulate the production of aviation gasolines with still greater freedom from knock-that is, of more than 100 octane number-as well as the development of power plants capable of using such knock-free fuels to advantage. There seems to be no special need for important changes in the other essential qualities of gasoline for aircraft. Vapor pressure may be lowered somewhat from the 7-pound limit of the present, and that would be an aid to fast-climbing highflying airplanes. Volatility may be changed somewhat also by raising the current limits a t the 10, 50, and 90 per cent points on the distillation curve. But such changes are minor. I n respect to high-flash aviation gasolines (the so-called safety fuels) the future is difficult to foresee, in part because there is still difference of opinion about how much such fuels can contribute to safety. But to whatever extent such fuels may be found useful, i t will demand the making of highoctane hydrocarbons boiling a t 300’ F. (149” C.) or more, for that is needed to give the required flash point of about 105’ F. (41’ C.). This again is a job for chemistry and chemical engineering because such high-boiling knock-free hydrocarbons are not plentiful in nature. It will be of material assistance in reaching the required degree of freedom from knock if the high-boiling hydrocarbons prepared can be of those structures in which tetraethyllead is especially effective as a knock suppressor (7).
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Fuels for Diesel Engines in Motor Transport
Lubricalqts
The use of Diesel fuels in automotive vehicles is still too new for experience to point further directions clearly. This is true even in respect t o the relative requirements for Diesel fuels as compared with gasoline. But whatever that relation may prove to be, it will perhaps not have much effect upon availability, for both gasoline and Diesel fuel come from the same source. I n general, it is to be expected that advances will be made in those properties of Diesel fuels in which improvements can give significant gains. There are perhaps three general types of service, or of Diesel engines, in motor transport: (1) The large, slowspeed engine is used, for instance, in marine service and is not very exacting in its fuel requirements; (2) the engines of intermediate size and speed are employed, for example, in railroad service and in large trucks; (3) the smaller high-speed Diesel engines are used in busses and in some trucks. What follows refers to the needs of the second and third classes of Diesel engines. Two important factors in which Diesel fuels may influence engine performance are ignition quality and volatility. Another but perhaps less important factor is fluidity, which may be considered as including viscosity, pour point, and cloud point. The relative effects of these various properties have not yet been fully evaluated. However, the Full-scale Engine Group, Automotive Diesel Fuels Division, of the Cooperative Fuel Research Committee is engaged in a cooperative program to correct this deficiency. The aim of their program is to evaluate in full-scale Diesel engines of the various current types the relative importance of variations in the essential properties of Diesel fuels-in ignition quality, in distillation range or volatility, and in viscosity. Nevertheless, present knowledge is definite enough to show, for instance, that high ignition quality is an aid to starting, t o smooth combustion, and in some instances t o smoke-free and odorless burning and to high fuel economy. This suggests that in the future, a t least for use in trucks and busses, Diesel fuels are likely to be much higher in cetane number than those of today. It has been suggested (4) that such increase i n cetane number may be only about 10 units above the present average of approximately 45. But it is perhaps not possible as yet to set any limit with certainty, especially in view of the part that new and improved refining methods developed by the chemist and the chemical engineer may play. It seems not unlikely that, when necessary, ignition quality may be adjusted to the needed level with the aid of chemical ignition promoters. Some of these are known, but whether they will ultimately be used in practice will depend upon whether they can be made a t once effective and cheap. It is known also that, a t least in Diesel engines of the kind used in automotive service, smoking tendency is associated with volatility or boiling range. It appears therefore that, although future engines may well be less sensitive t o volatility in this respect, there will always need to be some upper limits on the boiling range of Diesel fuels used in the automotive type of motor transport. A factor in favor of setting volatility as low as possible is the higher heating value per gallon which the less volatile fuels usually have. I n respect to viscosity, future requirements are not likely to be rigid; but wherever the climate is cold, pour point and cloud point will necessarily have to be suitably low. As a minimum, Diesel engines in automotive service will apparently continue to need a carefully refined distillate fuel which is clean and free of gum or gum-forming components a n d which will burn completely without residue. Beyond these general guesses, it does not seem possible to trace future fuel needs for Diesel engines in motor transport.
To fulfill its function, a lubricant must effectively reduce friction between adjacent surfaces, sometimes a t pressures extremely high. It must also aid in carrying away heat and, in so doing, get hot itself. It must accomplish these ends without being too viscous for use a t low temperatures, without forming enough acid through oxidation to cause corrosion of parts, and without producing harmful deposits, such as varnish, sludge, or carbon. These are the principal items in respect to which past improvements in lubricants have been made and with which needs for further advances will be concerned. Providing lubricants to fulfill these exacting conditions is a chemical problem which, in spite of the considerable advances made thus far, is not yet completely solved. One of the primary needs of the future is a better understanding of the chemistry and physics of lubrication, and of the relation between the chemical constitution of compounds and their suitability as lubricants. New lubricating problems have recently been introduced by the more severe service to which gasoline engines are subjected today both in the air and on the ground, by the extension of the use of Diesel engines in motor transport and by the increased use in rear axles of hypoid gears which subject metal surfaces to rubbing action a t extremely high pressures. It is only through chemistry that these new problems have been met in a practical way. The use of hypoid axle gears has been made possible only because of the discovery of chemical addition agents which, by contributing extreme pressure characteristics to oil, permit parts to move on one another a t pressures amazingly high (20). There seems to be need for still further improvements in the stability of lubricating oils, or in their resistance t o oxidation under those conditions of service in which high operative temperatures are met; and no doubt such improvements will be made. The newer chemical processes of refining lubricating oils, such as selective extraction of unwanted com-
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ness of the cooling process, and increase knock, and to the lacquers, asphaltenes, and troublesome sludges that collect in other parts of the engine, such as on piston rings and on nearly every part of the engine that is bathed by the oil (18). A step in this direction has been made in recent years through the use of various chemical detergents. These compounds, one class of which consists of certain metallic soaps, were introduced originally because they purge Diesel engines of deposits, especially on piston rings, formed by incomplete combustion of fuel and oil in the combustion chamber. But detergents have since been found useful also in gasoline engines, especially in those which run under severe conditions of service. However, some of the detergent compounds are strong oxidation catalysts and must be used in conjunction with oxidation inhibitors; otherwise corrosion of engine parts by acids formed through oxidation is likely to occur. A further chemical problem sometimes arises from the breakdown of the detergent itself which may cause corrosion in the heavily loaded areas of bearings. More knowledge is needed in the field of detergency, and there appears to be a great deal of room for further advance. Finally, there is vital need for simpler methods of evaluating in advance the service behavior of lubricants. The developments of recent years have made the older laboratory methods of inspection inadequate, if not almost useless in some instances. The result is that for some of the newer oils the only tests that can be depended upon are those made in actual service. But service tests are necessarily costly and slow; an advance which is badly needed is the development of laboratory tests for lubricants that will be more truly indicative of behavior in service.
Conclusion Courtesy, Standard Oil Development Company -%~ASSIVE CONCRETE STALLS EXCLOSE THE H E A V Y STEEL
REACTION CHAMBERS WHEREHYDROGENATION TAKES PLACE
ponents by treatment with chemical solvents, greatly improve oils in some respects but often take from them some constituents which have to do with resistance to oxidation or to the formation within them of acids, sludges, and other decomposition products. This shortcoming can be corrected by adding to the oil, after refining, chemical inhibitors of oxidation (16, 18) and in some instances chemical detergents (17, 18). These developments have been of great advantage in equipment which has t o meet particularly severe conditions of service. But the whole subject of controlling the properties of lubricants by chemical means is new, and a much better understanding of it is needed. Still more effective means of reducing change of viscosity with temperature would be an aid in lubricating motor vehicles over the wide ranges of temperature a t which they have to be operated. Already the slope of the viscositytemperature curve has been reduced considerably by chemical processes of refining and by the addition of large-molecule compounds produced by chemical synthesis (16). Synthetic compounds are sometimes used also t o lower the pour point of oils, or the temperature a t which they cease to flow. Other chemical compounds are added to reduce wear and t o increase load-carrying ability under the conditions called “boundary” lubrication. The latter, sometimes termed “oiliness” agents, are related in some respects to the extreme presvure compounds, previously mentioned, but the two classes of cornpounds are not identical (16, 80). All of them appear to be capable of further improvement t o meet better the needs of motor transport. Wanted also are still more effective means of reducing engine deposits. This applies both to the cokelike solids that collect inside the combustion chamber. reduce the effective-
Thus, in every phase of fuel and oil the principal need for the future is more knowledge. Material resources appear to be adequate. The primary requirements are more perfect knowledge of the chemistry of fuels and lubricants, of the kinds of compounds best suited for each purpose, of the methods of converting the raw materials into those forms at the lowest possible cost, and of the best means of utilining the improved products in motor transport with maximum efficiency.
Literature Cited Am. Petroleum Inst., “American Petroleum Industry”, Chap. I1
(1935). Am. Petroleum Inst., “Petroleum Facts and Figures”, 1937, 1939. Barnard, D. P., S. A . E . Journal, 41,415 (1937). Barnard, D. P., and Fox, A. H . , Am. SOC. Testing Materials, S y m p o s k ~ mo n New Materials in Transportation, 1940, 66. Brown, B. K., News E d . (Am. Chem. SOC.),18,347 (1940). Cleveland Trust Co., Business Bull. 21 (March 15, 1940). Cramer, P.L.,and Campbell, J . bI., IND.END.CHEM.,29, 234 (1937). Egloff, Gustav, Ibid., 30, 1091 (1938). Eisner, Sprunk, Clarke, Fein, Fisher, and Storch, U. S . Bur. Mines, Rept. Investigation 3498 (1940). Fieldner, A. C., Proc. Am. SOC.Testing Materials, 37,Part 1, 31 (1937). Fieldner, A. C., and Brewer, R. E., U. S. Bur. Mines, Circ. 7105 (1940). Gruse, W.A.,and Livingstone, C. J., Am. SOC.Testing Materials, S y m p o s i u m on Lubricants, 1937,2. Heron, S . D., Proc. Am. Petroleum Inst., I11 18, 84 (1937). Howard, F. A., Chem. & M e t . Eng., 46,751(1939). Lovell, W.G., and Campbell, J. M., Chem. Rev., 22, 159 (1938). Maverick, G.M . , and Sloane, R. G., Am. SOC.Testing. Materials, Sgmposium o n Lubricants, 1937,67. Neely, G. L., S. A . E . Journal, 45,485 (1939). Stewart, Moran, and Reiff, Am. SOC. Testing Materials, Symposium o n New Materials in Transportation, 1940, 92. Storch, H . H., and Fieldner, A. C., Mech. Eng., 61,605 (1939). Wolf, H. R., Proc. Am. Petroleum Inst., I11 20, 16 (1939). Work Projects Administration and U. S. Bur. of Mines, Rept. E-10,124 (1939).
