Leading Articlus in the Reviews. 



343 



THE LAW OF THE AIR. 



Mr. H. liK'a i;ii.\M Lelch writes on the jurisprudence 

 if the air, in the Forliiighlly for August. His discussion 

 I the private law leads to the conclusion that the 

 .arman is free to traverse the property of his neigh- 

 bour, to ho\er over and inspect or even photograpli 

 the premises below. He is responsible, however, for 

 damage that he may do, by falling or otherwise, to the 

 property he traverses. As to public law, the State may 

 provide for tiie collecting of custom dues, and for the 

 prevention of smuggling, of landing of infectious 

 patients, undesirable aliens, the inspection of forts, 

 arsenals, etc., and the operations of .\narchists. In 

 international law. in time of peace the air, as well as 

 the sea, is what the Roman jurists call a matter common 

 to all. 



SHALL WAR IN THE AIR BE ALLOWED ? 



In war, the question remains open. Is the air to 

 be made a theatre of war ? At present the prohibition 

 of aerial war was only signed by twenty-seven out of 

 forty-four Stales at the Second Hague Conference. 

 .\mong the non-signatory are all the great European 

 Powers e.xcept .\uslria and Great Britain, six other 

 1-^uropean States, and Japan : — 



The lime is ripe fur an uprising of public opinion to slay the 

 progress of lliis impending scourge. There could be no fairer 

 opporlunily for a crus.idc, or holy war. Aerial warfare is 

 inhuman, unnecessary, and baleful lo all ; even lo the rulers and 

 statesmen, who, ai trustees on behalf of others, to whom it is 

 still more hateful, give il ihcir support. The sands are running 

 .lut ; the longer the delay the less the chances of success. Why 

 .liould-not a loud and general protest from civilised humanity 

 ue heard ? The question is slill pending, and probably will nol 

 i.e decided until 1915, when ihe meeting of the Third /V.i^c- 

 I onference is due. What of all the Churches of the eivilise<l 

 world? What of all the I'eace societies? What of all thi 

 .\ssociations, mis-ionary and philanthropic, which are working 

 /.salously for the welfare of humanity, though often with incom- 

 mensurate rc^ults.' 



AIRCRAFT. 



In the Quarlerly linimv for July .Mr. Mervyn 

 O'Gorman treats of airships and aeroplanes. The air- 

 ship is eclipsed in interest by the aeroplane. 



tSKS OK THE AIRSHIl' AT SEA. 



Nevertheless, he .says : — 



It is noteworthy that in twelve years of work no Zeppelin 

 airship has s.icriliced a »iii;;lc aeronaut ; nor have our sm.ill 

 Kngli-'h oneN, with ihousands of miles to their credit. l''ur 

 >ca-work the airsliip may yet perform useful duties, since il can 

 come down 10 the waveJ with safety, ami cpiit them with great 

 ease. There ilns nol appear lo be any reason why a diueii or 

 more of small non-rigiil airship- should not be packed in the 

 hull of a suitable special ship in attendance on a fleet, and 

 carrying with it the necessary plunt for producing g.is, as 

 well as devices for mooring in the open ; for »uHiciciit experi- 

 .:nce nu« exists for mooring devices lobe considered practicable. 

 VARYING WlNli VELDCTTY TIIK CHIEF UIFFICLI.TV — 



The chief ditFn iilty of the aeroplane i.s the fait thai 

 the veloci'' "' "i'"' ^ iri''^ lo an .uiii/liii' divrci . Tlie 



diagrams show some twenty-seven changes of wmd- 

 speed in the minute. As the craft rises higher into the 

 air these wind-changes become less frequent, at any 

 rate in England : — 



The 300-yard level line roughly follows the profile of the 

 earth's surface ; and the winds below that level behave 

 generally in a similar way, save that winds attaining a certain 

 degree of velocity — say 20 miles an hour— dash through and 

 [last aerial obstacles till they are raiseil vertically on the wind- 

 ward side of any long range of hills. The impression given is 

 that such a range of hills causes a veuical deflection of a body 

 of the air some 2,000 yards thick before the hill is reached ; and 

 the vertical movement of a 20-mile wind extends lo a height of 

 1,000 yards above the hills. 



It is thought by Captain Ley, a serious experimenter on the 

 subject, ihal ihere are cerLiin dividing planes or levels or stages 

 other than the 300-yard level where special irregularity may 

 be met with in lingl'and, namely, somewhere about 700 yards 

 up, 1,000 yards up, and 1,300 yards up. These divisions 

 apparently occur at the loj) of the air-zone dominated by the 

 plains, the hill-ranges, and the mountains respectively ; and at 

 lliese dividing planes there are disturbances and sudden changes 

 of wind-speed. 



— VET OUR CHIEF FRIl^.ND. 

 At present, wind-pulsations are the chief enemy mat aeroplane 

 workers have to vamiuish ; but, as we progress, it will be borne 

 in upon us thai the only hojie we have of deriving the energy 

 of flight from the air itself depends upon utilising these very 

 pulsations. It is safe to say thai with the inception of long- 

 distance soaring we shall find that wind-pulsations are, on the 

 contrary, l/ie friend to whom we must look for the commercial 

 as distinct from the naval and military success of the flying 

 machine ; and this further triumph is, by all the signs, nol very 

 far beyond us. 



IN THE TWOPENNY TUBE. 



The Raihvay and Travel Munlhly gives an interesting 

 sketch of the Central London Railway. 



WHITEWASHI.NO UV MOTOR. 



.\iiiung the curious items of information given one 

 or two may be quoted : — 



The whole of the tunnels of the Central London Kailway are 

 periodically linie-whited ; a mr)tor-car having been liitcit up 

 with an ingenious apparatu-i which effectively sprays with lime 

 li.|iiid ihe whole of the interior of the lunnel, as il journeys from 

 end lo end of the line. 



A DANGER-SIGNAL THAT STOPS TRAINS. 



.\ very ingenious method of automatically prevent- 

 ing a train passing danger-signals is thus described :— 



(Jn the side of the bogie there is a cock « ith a rubber Iiom- 

 attached. This cock is connected to the air-pressure pipe of Ih.. 

 Weslinghouse br.ake, with which the trains arc fitted. Thi 

 cock has a lever projecting downwards, and if from any cause a 

 train were to lun past a signal which is at "danger," this leVcr 

 would strike against a trip Ireiulle at the side of the rails, thi 

 tock being thus opene<l, thereby automatically applying tli. 

 brakes .m all wheels of the train, anil bringing it to a standstill 

 At the same time, by means of a "control circuit governor,' 

 the current would be cut ofl' the motors. When the signal 1 

 lowered, the ireadle is lowered, «o that the " Irip cock," as it i~ 

 calleil, passes without touching. The lever is fixe.1 on the righi 

 sitic of the line, no as lo work the trip cock on the leading car. 



During the year nn 1 over eighteen million passenger^ 



wrn- carried on this line. 



