NATURE 



197 



THURSDAY, AUGUST 18, 1910. 



INTERNAL-COMBUSTION ENGINES. 

 The Design and Construction of Internal Combustion 

 Engines. A Handbook for Designers and Builders 

 of Gas and Oil Engines. By Hugo Giildner. 

 Translated from the second revised edition, with 

 additions on American engines, by Prof. \\. 

 Diederichs. Pp. xix + 672. (London : Constable 

 and Co., Ltd., 1910.) Price 425. net. 



THIS work is the most complete and elaborate 

 treatise on the gas-engine which has ever been 

 published, as will be realised when it is stated that 

 there are 664 pages of comparatively small-type letter- 

 press, 728 figures, and 36 folding plates. There is 

 a certain amount of the usual padding, namely, photo- 

 graphic reproductions of large and small gas-engines 

 of various makes, as well as records of tests, but 

 there is also a large amount of original work and 

 practical information which, owing to the position of 

 the author, viz., chief engineer and director of the 

 Giildner Motoren Gesellschaft, must be regarded as of 

 great value. In the preface to the first edition, the 

 author states : — ■ 



" Germany's gas-engine industry justly enjoys an 

 international reputation . . . everything that has 

 served to lay the foundation of the industry and that 

 has helped to make it vital and important is either 

 the product of German thought, or was first prac- 

 tically realised on German soil." 



It is not surprising, therefore, that the work reflects 

 German practice. 



The book is translated into English by Prof. H. 

 Diederichs, of Cornell L^niversity, and he has entirely 

 omitted the first part of the German edition, which 

 treats of the history of the gas-engine, and has sub- 

 stituted therefor descriptions of, and information 

 relating to, American gas-engines. The author says 

 that his principal object in writing this book was to 

 make it "serve as an every-day working guide to the 

 designer and constructor," and to follow out this object 

 he has adopted the somewhat unusual feature of giving 

 dimensioned drawings, not only of complete engines 

 or producers, but of various parts. These drawings 

 will undoubtedly be found to be of the greatest use 

 to many designers and also to purchasers of engines 

 who may wish to verify whether a proposed engine 

 is correctly designed or not. 



The work is divided into four parts and an appendix. 

 The first part deals with the various methods of 

 operating gas-engines and the gas-engine cycles; the 

 second part with the design and construction of in- 

 ternal-combustion engines; the third with the erection 

 and tests of modern internal-conibustion engines ; the 

 fourth with gas-engine fuels and combustion in gas- 

 engines; and the appendix with various theoretical 

 matters relating to thermodynamics and thermo- 

 chemistry, as well as with certain details derived from 

 practice. , 



In dealing w^th the constant-volume cycle, the 

 author investigates the question of the maximum 

 compression that should be practicallv adopted, tak- 

 NO. 2129, VOL. 84] 



ing into consideration the theoretical thermal efficiency 

 based on comparatively recent data of the variation of 

 specific heat with temperature, as well as the efficiency 

 ratio and mechanical efficiency, and finds that the 

 economic limit of maximum compression lies between 

 2iolb. and 28olb. per square inch, a conclusion 

 which, although these pressures are somewhat higher, 

 is substantially in agreement with the experimental 

 work of Prof. Burstall. 



A critical comparison of the four-cycle and two- 

 cvcle engines is made, and the author comes to the 

 conclusion that the four-cycle engine can only be 

 considered " as a makeshift until an efficient and trust- 

 worthy two-cycle machine appears on the market " ; 

 he also discusses the question of compounding, and 

 states that " it will remain without promise in gas- 

 engine construction." The design of the various parts 

 of gas-engines is gone into in the very fullest manner, 

 and numerical examples are worked out in great 

 detail ; some interesting photographs are given show- 

 ing the effect of weak frame construction and of 

 imperfectly designed crank-shafts. A great deal of 

 information respecting the type of material to use 

 for the various parts of gas-engines is given, and in 

 the matter of connecting-rods, while stating that soft 

 steel is usually employed, the author says that the 

 use of cast-steel is on the increase. The design of 

 inlet and exhaust valves is given in great detail, and 

 the various methods of water-cooling are described. 

 Amongst the latter is an interesting arrangement de- 

 signed by Pawlikowsky, in which the water-pipe is 

 stationary and the water is led through the valve 

 spindle, which is large enough to be bored out to 

 admit the inlet pipe with a space around it through 

 which the hot water can find its way back. The 

 design of fly-wheels is discussed at considerable 

 length, and numerous tangential effort diagrams for 

 various types and designs of gas-engines are given, 

 and the results of various calculations are embodied 

 in a series of curves by which the required weight 

 of rim of a flv-wheel can be ascertained under various 

 conditions occurring in practice. 



In respect of gas-producers, the author appears to 

 favour the suction-producer in preference to pressure- 

 producers, and says that the former have almost en- 

 tirelv displaced the older form. This statement is 

 made without any reference to the size of the engine 

 to be supplied with gas, and cannot, therefore, be 

 regarded as conforming with present practice, in- 

 which the large gas-engines are supplied with gas. 

 from pressure-producers. Numerous designs of suc- 

 tion-producers are described, none of them larger than 

 600 b.h.p.. and there is only a passing reference to 

 pressure-producers. 



At the beginning of part iii., much detailed.informa- 

 tion is given in respect of the capital cost and cost 

 of erection and running of gas-engine installations, 

 and all this information is collected together in a 

 tabular form, giving all the various heads of expendi- 

 ture for engines varying from 5 b.h.p. to 200 b.h.p., 

 both when using illuminating gas and suction gas. 

 It is interesting to note that the total operating costs 

 for 5 b.h.p. are the same for both kinds of gas, but 



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