806 SCIENTIFIC AMERICAN Octoher J�, 1918 Rudolf Diesel: An Appreciation The Significance of a Great Inventor's Work By Henry Harrison Suplee HERE are inventors and inventors! operation. The motor of Diesel, on the contrary, was England and America, are interested in this modern T The old-time idea of an inventor was a man who, first worked out wholly on paper, as a rational applica­ power machine. It propels practically all the effective ><uddenly, in some occult manner, conceived the idea of tion of theoretical principles, and then and not until submarine vessels in service, it is entering into the mer­ :,;omething new, wonderful, and valuable, and who then then, was a machine built. At this time the best ther­ chant marine, and unless the ship on the water is super­ spent the rest of his life trying to get capitalists inter­ mal efficiency of the steam engine, and that in large seded by the ship in the air, it must enter the naval ested in it; a man who was lucky if he did not die poor units, was about 15 per cent. The early Diesel engines service of all progressive powers. and enrich others after he was gone_ of small size, 20 to 30 horse-power, showed immediately The contrast between this modern method of produc­ The modern inventor is something quite otherwise; an efficiency of more than 30 per cent; and the thermal ing power from fuel �ith the older machine, the steam a trained engineer, who, perceiving the defect in some efficiency, or percentage of total heat value in the fuel engine, is interesting. Instead of burning fuel ineffi­ department of engineering work, directs his mind to converted into power in the cylinder, in present Diesel ciently under a boiler, to convert water inefficiently the solution of the problem, and, bringing to it ample engines is from 42 to 48 per cent, or nearly three times into steam, conveyed inefficiently through a pipe, to be theoretical knowledge, carefully and accurately works the efficiency of the steam engine, and double that of expanded inefficiently in a cylinder, the fuel is injected out practically the application of the theory to definite the ordinary gas engine. Even when the frictional as a spray into a mass of dense, highly heated air, in success. Such modern invention is typified by the work losses in the mechanism of the machine are deducted, the very cylinder where the power is to be generated. of Rudolf Diesel. the actual efficiency in the power available for useful Clo:,;ely crowded into contact with ample air for its com­ In the summer of 1897, the Verein deutscher lngeni­ work has reached about 35 per cent, and this because plete combustion, the fuel is completely burned to the eure was holding its convention at gaseous state, without any residue. Cassel. During the meeting the pushing the piston before it to make members of this important engi­ room for its increasing volume and neering society were invited to wit­ that of the expanding air which it ness the operation of a new type of is heating, but without increase in heat motor, the result of the appli­ pressure. Then, expanding along an cation of modern thermodynamic adiabatic curve, it yields up energy principles to the problem of secur­ which, in the cruder machine, was ing maximum efficiency in the de­ largely dissipated uselessly, and, Yelopment of mechanical energy like an expanded spring, is released. from the combustion of liquid fuel. There is probably no more labori­ That motor was the Diesel engine. ous and exhausting work demanded _\8 then shown and enthusiastically of human beings than that required ndmired it was practically the same in the stokehold of a great steamer; as that which is now known all over and no more impressive demonstra­ the world as the most efficient heat tion of the result of the work of motor in existence, and the greatest Rudolf Diesel can be given than to advance in the generation of power compare the infernos before the fur­ from heat since the invention of the naces of a marine boiler with the separate condenser by Watt. cleanly, cool, and silent engine room Rudolf Diesel, born in Paris in of such a vessel as the "Selandia" 1858 of Bavarian parents, received with its Diesel engines. his early education in the French In the University of Glasgow capital, and thus acquired the easy there is cherished the model of the fluency in the French language Newcomen engine upon w h i c h which made him so acceptable a James Watt was working when he speaker before the meetings of the conceived the idea of the separate Societe des lngenieurs Civils de condenser. In the museum at South France. The outbreak of the war Kensington there are some frag­ in 1870 rendered it necessary for his ments of Stephenson's "Rocket." parents to leave France, and a por­ There is cause for gratification that tion of the time after this was spent in the new buildings of the great in England, so that, to a thorough German Museum at MUnich, the knowledge of German and French, original Diesel engine is preserved there was added an equally great as a monument of the result of the proficiency in English, rendering the union of theory and practice. young man a true cosmopolitan in t raining and thought. A course in A Hydro - aeroplane Flight III e c han i c a I engineering at the Miinich Polytechnic, under such From Newport to New York masters as Schroter, in mechanics, O N September 29th WllIiam and von Linde, in thermodynamics, Thaw of Pittsburgh and Glea­ was followed by an excellent busi­ son Macgordon started' from New­ ness training in charge of the Linde port in a Curtiss flYing boat. .They refrigerating machine interests in landed on Oakwood Beach, Staten Paris. Thus there were brought to Island, on OctobElf, ,:6th.' The most the attention of this acute and eventful porJ,iolt ettbli trip was the ' broad intelligence the fundamental journey fro� MOFrl�.' C6ve, Conn., to Diesel, the inventor of the Diesel engine. problems in the relations between Staten Island. InfiYin� down the thermal and mechanical energy in East River the aviators, had to pass connection with gases under high pressure. The first of the scientific application of theoretical principles under three bridges, which they did with ease. Indeed, result of this combination of theoretical and practical to the design of a rational heat motor. the bridges gave them less concern than the smoke 'and ideas to be given ·to the public was a small book en­ Apart from the adoption of an efficient cycle, and the cinders in the atmosphere of New York. This is one of titled "The Theory and Construction of a Rational Heat use of high compression ratios, the Diesel engine has the longest hydro-aeroplane journeys thus far made in Motor," this appearing in 1893. Here we see the scien­ accomplished an important commercial result in two the United States. tific man, working. mentally to consider the necessary ways: the heat of the compression is sufficient to ignite elements of a rational machine for converting heat into the fuel charge directly in the cylinder, thus eliminat­ An Official Register of Selected Plants will shortly work. He approached the subject along the lines of ing altogether the carbureter, that source of so many be established in Hungary, if. the recommendations of his master, von Linde, considering the various cycles annoyances in ordinary combustion engines; while the E. Grabner, director of the Royal Hungarian Institute possible, and selecting the so-called Carnot cycle as absence of any ignitable charge during the compres­ of Plant Selection at Magyarovar, are accepted by the offering the possibility theoretically considered, of at­ sion stroke renders back-firing impossible. government. The objects of this re�ster will be, on taining the maximum thermal efficiency. Having chosen The intimate admixture of the pulverized liquid fuel, the one hand, to protect the lights of plant-breeders the cycle, the best methods of attaining it were con­ into the midst ·of highly compressed air much above and prohibit the illegal sale of varieties improved by sidered, and with these came also the knowledge of the the temperature of ignition, also insures complete Com­ them, and, ·on the other, to afford every guarantee to importance of operating with a high compression ratio bustion, even when heavy and ordinarily difficult fuels the purchaser of the strict selection of the variety which in connection with high efficiency. are used, so that all liquid fuels may be used indiffer­ has produced the seeds he wishes to buy. This guarantee ' These things determined, there followed a study of ently, from the light gasoline to the heavy distlllate resi­ will not extend to the quality of the seeds (e. g., their the best practical approximations which might be ex­ dues. Gas tar is readily and fully consumed, and vege­ power of germination), nor to the value of the crop, but pected to these theoretical conditions. table oils, such as peanut oil or castor oil, are freely merely to the identity and purity of the variety. Detailed We see here a complete reversal of the older ideas of converted into power in the Diesel engine. The revolu­ plans for this undertaking have been submitted to the inventors, of those men who, having conceived some tion which such a machine is creating in the develop­ Ministry of Agriculture, including provision for the kind of a machine, proceed to try it out experimentally, ment of power must appear.