404 



NATURE 



[July 13, 1916 



plane is next dealt with, the advantage of the 

 small target area offered is pointed out, and the 

 possibility of armouring for low-altitude flying 

 discussed. The fact that an insufficiency of 



armour is worse than none is strongly insisted 

 upon. 



Next follows a discussion of the principle of 

 concentration, with numerous examples of the 



NO. 2437, VOL. 97] 



author's n-square law. This section does not call 

 for much comment here. 



Mr. Lanchester expresses the opinion that 

 treaty restrictions framed for the other arms of 

 the Service should not apply to the 

 new arm, particularly pointing out 

 that expanding bullets could be used 

 with great effect in the destruction 

 of the spars and struts of aeroplanes 

 by gunfire. The question of the 

 -^ difficulty of aiming bombs is dealt 

 J with, and Mr. Lanchester thinks 



1 that the gun will eventually displace 

 c the bomb in the armament of air- 



« craft. 



u The subject of naval aeronautics 



< receives some attention, the great 



"g difference of the conditions from 



2 those of military aeronautics being 

 specially remarked upon. The great 



% value of aircraft for combating sub- 

 ^ marines is mentioned, and the ques- 

 '^_ tion of the relative merits of sea- 

 ^ planes and aeroplanes carried by 

 ^ pontoon ships is discussed. It is 

 s stated that the pontoon ship offers 

 ■;; better alighting facilities and enables 

 - faster machines to be used. 

 ^ A great deal of space is devoted to 



5 the probable tactics of large fleets of 

 ^ aeroplanes. This subject gives Mr. 

 •= Lanchester ample scope for his lively 

 I imagination, and his treatment of 

 J the subject is speculative in the 

 S extreme. It seems scarcely possible 



1 to define aeronautical tactics in such 



2 an extensive fashion at such an early 

 I stage in the development of the new 

 5 arm. 



■;; Mr. Lanchester completes his 



" book with a consideration of the 

 i present position, pointing out with 

 "g no uncertain voice that the British 



3 aeroplane of to-day is better aero- 

 dynamically, more stable, more 



^ robust, and more weatherproof than 

 pi the enemy's best machines, and in 

 "o all ways better fitted for service con- 

 ? ditions. It is stated that there was 

 s no good gun-carrying aeroplane in 

 1 existence at the commencement of 

 I the war, and that the progress made 

 ■g has been astonishing. Reference is 

 S made to the work of the Royal Air- 

 X. craft Factory, special praise being 

 j| given to the full-scale experimental 

 work of the late Mr. E. T. Busk. 

 The scientific research work of the 

 National Physical Laboratory re- 

 ceives consideration, and Mr. Lan- 

 chester reiterates that in scientific 

 knowledge we are well ahead of all 

 other nations. A board of aeronautical construc- 

 tion is advocated, as apart from the present ad- 

 visory committee. 



There is a brief appendix giving some details 



