REVIEWS 331 



The author is an acknowledged authority on aerodynamics and we feel 

 this throughout — from the point where he deals with the " Principles of 

 FUght " (p. 18) to " The Stability of the Motions of Aircraft," which forms 

 the subject-matter of chapter x (and last). Further than this, Mr. Bairstow 

 knows and appreciates the limitations of those engaged in practice, and 

 interprets the results of research, gives approximate solutions to awkward 

 equations, and illustrates results graphically wherever possible. Explana- 

 tions and actual weights, dimensions, etc., are freely given, and in many 

 places, after what, to many, will be severe mathematical flights, the reader 

 finds himself brought gently to earth by a practical application. 



Every engineering graduate of the future should have a good knowledge 

 of aerodynamics, but it would be impossible to expect other than those who 

 specialise in aircraft to assimilate the material in the present book. Is 

 it too much to ask the author to issue a further volume based on the pre- 

 sent one of about one-fifth the size and one-quarter the price ? It would 

 be as great a boon to the engineering student as the present volume is to 

 those interested or engaged in the industry. 



J. Wemyss Anderson. 



The Theory and Practice of Aeroplane Design. By S. T. G. Andrews, B.Sc. 

 (Engineering), London, and S. F. Benson, B.Sc. (Engineering), 

 London. [Pp. viii + 454, with 308 figures and 74 tables.] (London: 

 Chapman & Hall, 1920. Price 15s. 6d. net.) 



This volume is issued under what is known as " The Directly Useful |D.U.| 

 Technical Series," and deals, not only with the design of the various parts — 

 wings, fuselage, chassis, air-screw and control surfaces — but treats of the 

 stability, performance, and lay-out of machines, together with a chapter on 

 '' The General Trend of Aeroplane Design." 



The work throughout is reliable and of the utmost value to engineers 

 engaged in, and for students training to enter, the industry, and the follow- 

 ing suggestions are meant " for improvements in future editions " rather 

 than critical of the present volume. In the first place the title should be 

 " Aeroplane Design." The words " Theory and Practice " might have 

 been in order ten years ago — to-day they are out of place. 



Then, again, a book on design must not only deal with up-to-date work, 

 but must be suggestive from the first to the last page. A chapter on the 

 general trend is not sufficient. For instance. Fig. 155 and Table XXIX deal 

 with actual stream-line strut sections — and they are very varied. What is 

 the reader to do ? Which is he to use ? Is the " Beta " section (p. 213) 

 the last word ? Mention should have been made and results given of the 

 Hele-Shaw method of investigation, which would have given the designer 

 plenty of food for reflection, with possible development. Finally, the work 

 on air-screw design is marred by the statement on p. 7 that " the func- 

 tion of the air-screw is to transform the torque on the engine crank-shaft 

 into a propulsive thrust by discharging backwards the air through which 

 it moves ; and whose resultant reaction enables the necessary forward 

 momentum to be secured." This sentence requires drastic rewording — the 

 " discharging of air backwards " is not a function of the air-screw. 



J. Wemyss Anderson. 



Aircraft in Peace and the Law. By J. M. Spaight, O.B.E., LL.D. [Pp. 

 viii + 234.] (London : Macmillan & Co., 1919. Price 8s. 6d. net.) 



The author, in a very able manner, has dealt with the more important 

 questions— chiefly of law — that must arise with the development of civil 

 aerial transport both at home and abroad. 



