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NATURE 



[July 12, 1917 



Viscount Bryce in the House of Lords on July lo, the 

 Duke of Marl'boroug-h said that the editor would be 

 entitled to consider what was essential and what could 

 properly be omitted from the Bulhtin. 



In view of the cancellation of the annual meeting 

 of the British Association, it has been necessary to 

 make special arrangements for carrying on the 

 Association's current work. Meetings of the organis- 

 ing committees of the various sections, the delegates 

 of corresponding societies, the committee of recom- 

 mendations, and the general committee have there- 

 fore been held. It has been decided to continue Sir 

 Arthur Evans in the presidency for another year, 

 while the Hon. Sir C. A. Parsons, who would have 

 presided over this year's meeting, will do so at the 

 meeting which it is hoped will take place as arranged 

 at Cardiff next year. The meeting this year would 

 have been at Bournemouth, and that borough has 

 repeated its invitation, which has been accepted, for 

 iqig. Grants amounting to 286^ were made in aid 

 of such researches as were regarded as essential to 

 carry on, having regard to present conditions. The 

 new members of the council of the Association are 

 Dr. E. F. Armstrong, Mr. J. H. Jeans, Prof. A. 

 Keith, Prof. W. H. Perkin, and Mr. W. Whitaker. 



Le Temi)s of June 2q contains a full report of the 

 discourse delivered by M. Alfred Capus on his election 

 to the French Academy in the place vacant by the 

 death of Henri Poincare. The election of a man of 

 letters to fill the place of a man of science might 

 strike some people as strange, but M. Capus remarks 

 that in France knowledge has never been reserved 

 for some few "mandarins" any more than it has 

 required an obscure language and esoteric formulae, 

 and recalled the example of Descartes. In fact, since 

 the seventeenth century the education of the French 

 middle class has always kept up both the scientific 

 and the literary tendency. It is the custom for such a 

 discourse to be devoted to the work and life of the 

 particular predecessor, and so Poincar^'s works, and 

 particularly his books, "La Science et I'Hypothese " 

 and "La Valeur de la Science," are described with a 

 light touch that, owing perhaps to its being a national 

 characteristic, is not unlike the touch of Poincar^ 

 himself when he was dealing with subjects with 

 which he was not very well acquainted. 



It was reported in the Daily Chronicle of June ao 

 that the Duchess of Somerset had stated that "as a 

 result of gunfire sixty kinds of migratory birds had 

 ceased to visit Britain." This report was so definite 

 and remarkable that we communicated with her 

 Grace, who informs us that what she stated was 

 that her g-ardeners had said that this year there was 

 only one bird for every sixty which were here last year, 

 "from the effects of cold weather, etc." As. many 

 general statements have been made recently referring 

 to the alleged absence of migratory birds in conse- 

 quence of heavy gunfire and a prolonged winter, we 

 communicated with Dr. W. Eagle Clarke, keeper 

 of the Natural History Department of the Royal 

 Scottish Museum, Edinburgh, and a leading authority 

 upon bird migration. Dr. Clarke says : " Not a 

 single species of regular migratory bird has been 

 absent from Britain since the war broke out.' I am 

 familiar with the whole of the data, from all parts 

 of Scotland, relating to our seasonal bird-visitors for 

 the past twenty-five years, and am able to state that 

 this summer all our regular spring migrants are 

 with us in their usual abundance. I have no informa- 

 tion relating to the effect of gunfire on bird migration 

 other than that so far as our islands are concerned 

 it has had no influence whatever on the comings 

 and goings of our feathered visitors." 



NO. 2489, VOL. 99] 



When a bomb* is dropped from a moving aeroplane 

 the i>oint at which it strikes the earth depends 

 primarily on its altitude above and speed with respect f 

 to the earth's" surface, and to a smaller extent on the 

 speed of the wind and the mass and surface of the 

 bomb. In order to allow the aviator to drop his 

 bomb on a given object, the most recent German 

 aeroplanes are provided with an instrument made by 

 Goerz which consists of a telescope kept vertical by 

 means of a bubble of air in the eyepiece. By means 

 of a movable prism below the objective the observer 

 can adjust his instrument so that he sees through it 

 objects at a given angle ahead or in the rear. The » 

 instrument is generally used when the aeroplane is 

 moving against the wind. From the aneroid reading 

 of the height of the aeroplane and the time taken to 

 get vertically over an object seen previously 22-5° 

 ahead, the speed of the aeroplane is known. The 

 speed of the engine gives the speed of the aeroplane 

 through the air, so that the speed of the air is known, 

 and for a given bomb the angle at which the line of 

 sight of the instrument must be set ahead in order 

 that a bomb released when the object is seen in the 

 telescope may strike that object is also known. Varia- 

 tions of direction of flight of the aeroplane and of 

 strength and direction of the wind cause errors which 

 are to some extent eliminated by further devices which 

 will be found described in La Nature for June 19. 



An interesting article appears in the current number 

 of the Fortnightly Review under the title "The Civil 

 Aerial Transport Committee : A Milestone in the His- 

 tory of Flight." The question of the use of aircraft 

 for commercial purposes, and especially for mail ser- 

 vices, is treated in a very clear and practical manner. 

 The authors of the article — Mr. C. Grahame-White and 

 Mr. Harry Harper — consider that our present know- 

 ledge' of aeronautics is sufficient to enable a machine 

 carrying one ton of mails at 100 miles per hour to be 

 built with ease. It is pointed out that the weather 

 would have less effect on an aerial mail than is some- 

 times supposed, as a heavy machine is less susceptible 

 to gusts than the earlier light and under-powered 

 aeroplanes. A machine travelling at 200 miles per 

 hour is pictured as a future possibility, but this is cer- 

 tainly out of the question with present-day engines. 

 Future research will doubtless produce lighter petrol 

 motors, but it remains to be seen whether Mr. Grahame- 

 White's suggested gas turbine, with a weight of half 

 a pound per borse-power, will ever become a practical 

 proposition If such an engine were ever produced, 

 the future of commercial aviation would indeed be 

 bright with promise. The question of landing grounds 

 is discussed at some length, and it is pointed out that 

 the establishment of an aerial mail must be preceded 

 by the setting out of a series of good landing grounds 

 at short intervals along the route. This can, of course, 

 be easily done, and the provision of suitable ground 

 signs by day and night to enable the aviators to locate 

 themselves should offer no difficulties of practical 

 solution. Much stress is laid on the necessity of spend- 

 ing considerable sums on scientific research to eluci- 

 date any technical questions that may arise, in order 

 that the establishment of a commercial air service may 

 be attended with as few accidents and as little loss 

 of life as possible. 



The committee appointed by the Institute of 

 Bankers to consider the question of the adoption of 

 a decimal coinage and the metric system of weights 

 and measures has issued its report. .^s regards 

 weights and measures, the comm.ittee is of opinion 

 that the existing system in this country is an obstacle 

 .in the way of ihe extension of our foreign trade, 

 especially of our export trade, and as a first step 



