684 



NATURE 



[No\i.>ii>i-.K lO, 1923 



it conveys at first jrlance of Iwing a highly tfchnical 

 treatise, will prolwbly prove rather overwlidtning, 

 though it is to »>e hofied tlmt these factors will not be 

 detrimental to a wide circulation and thus defeat the 

 main objects of its production. 



The work is much more than a mere compilation. 

 Fifteen specialists in different branches of the industry 

 have contributed to its undertakin>?, and as a standard 

 book of reference it thus stands alone. No one man, 

 be he a Heaven-sent genius, can comprehend adequately 

 the intricate ramifications of the oil-industry of to-day ; 

 no written work, the product of a single human brain, 

 can possibly do justice to a subject the rapid evolution 

 of which depends on progress along so many highly 

 specialised branches of natural science. 



Yet, like all things material, there are obvious dis- 

 advantages in the co-ordinated essays forming the 

 substance of this work. Not the least of these is the 

 strong American bias noted throughout ; also the 

 apparent lack of appreciation of problems which beset 

 others than those engaged in the American petroleum 

 industry. After all, though we readily admit United 

 States supremacy if measured in terms of annual oil 

 production, the Old Worid may surely claim a modest 

 share in the research and invention which have contri- 

 buted to the wonderful progress of petroleum tech- 

 nology within the last half-century. American in- 

 dustrial problems are not necessarily Eurasian, nor are 

 American solutions to those problems necessarily final 

 to foreign operators. Hence without for one moment 

 casting any reflections on the high merit of the work, 

 it seems to us that a far wider purpose (thus a corre- 

 spondingly greater value) would have been served had 

 the book been planned on a more broad-minded, inter- 

 national basis, with something more than passing 

 mention of oil affairs external to the United States. 



This international element, had it existed, would 

 have balanced the detailed description of the strati- 

 graphy, structures and oil occurrences of North 

 America with something more than a few cursory para- 

 graphs of similar Eurasian criteria, as given by Mr. 

 F. G. Clapp, responsible for the first section on " The 

 Occurrence of Petroleum." Mr. F. H. Lahee, in the 

 second section on " Field Methods in Petroleum 

 Geology," would have been compelled to demand (with 

 great advantage to the section) more space to deal with 

 methods applicable to other than simple phases of 

 geological surveying. Mr. R. G. Smith would likewise 

 have included some description of the impregnated 

 sediments well-known in European industries in his 

 section on " Asphalt," while Mr. D. E. Day's section 

 on " Oil Shale " would have profited by some account 

 of European occurrences and methods. Perhaps these, 

 and similar omissions, will be remedied in future 

 NO. 2819. VOL. I 12] 



editions of the work ; at all events most of the othi i 

 sections are so good that it would be a pity if this \\'vx> 

 not done, thus making Day's " Petroleum Indust: 

 standard work in everj' sense of the word. 



H. B. MiLNKK. 



Friction. 



Our Bookshelf. 



Dr. T. E. Stun ton. 



By Dr. T. E. Stunton. Pp , ...j. 



(London : Longmans, Green and G)., Ltd., 1923.) 

 125. dd. net. 

 In recent years considerable advances have been mad<- 

 in our knowledge of lubrication, static friction, a- 

 resistance exerted by fluids on bodies moving li, 

 them. The importance which this knowledge luia for 

 engineers can scarcely be overestimated, and it is 

 fortunate that the man who has had the greatest shan- 

 in making these advances has been able to find lime to 

 write a complete account of the whole subject. 



In the term " friction," Dr. Stanton includes all the 

 agencies by which the moving parts of a machine art; 

 retarded and their energy dissipated. First of thestt 

 in importance comes fluid resistance, and the first 

 chapter is devoted to viscosity, the physical property 

 on which all fluid friction depends. The second 

 chapter, on the " External Friction of Fluids," opens 

 with an account of the application of Newton's principle 

 of dynamical similarity to fluid friction, and the results 

 of a wide range of experiments on the flow of fluids 

 through pipes are discussed from this point of \-iew. 

 The remarkably wide scope of the discussion of the 

 surface friction of fluids may be judged from the fa< i 

 that the friction may be estimated from exp)eriment,> 

 on the flow of liquids or gases in pipes, from direct 

 experiments, with sheets of metal exposed edgewise 

 in the wind, from meteorological observations, from 

 tidal data, and from observations of the velocity of the 

 wind close to the surface of a flat plate. All these 

 methods lead to nearly identical reshlts. 



Chapter iii. is devoted to the hydrodynamical theor\ 

 of lubrication ; recent work b summarised, and an 

 interesting account is given of the mathematical 

 considerations which led to the discover\- of Mitchell's 

 method of lubricating the thrust blocks of ;i st tamer's 

 propeller shaft. 



It is perhaps to be regretted that the dc ^ ..p...,.; of 

 Hardy and Doubleday's recent researches on boundary- 

 lubrication has been compressed into one paragraph. 

 The application of this work to engineering has not 

 yet gone ver>' far, but it seems probable that developn 

 ments in that direction may be expected in the near 

 future. The remaining chapters, on " Rolling Fric- 

 tion " and on " Friction and Heat Transmission," 

 introduce problems about which little is knowTi, but 

 perhaps for that very- reason they are as stimulating 

 as any in the book. 



The engineer will find useful information in ever>' 

 chapter, but it is to the physicist that the book makes 

 its strongest appeal. It would be difficult to pick out 

 from the whole range of physics a better example than 

 the subject of friction affords of the interdependence of 

 mathematical and experimental methods. The logical 

 way in which the matter is arranged serves to emphasise 

 this point of view. G. I. T. 



