THE NATIONAL GEOGRAPHIC MAGAZINE 



15 



field of battle gave to every one the terri- 

 ble sensation of being spied upon by an 

 adversary who inflicted blows from an in- 

 visible source. 



ARTILLERISTS APPEALED TO AVIATORS 



Artillery ammunition being particularly 

 scarce, it was important to fire only on 

 reliable information and at objectives, 

 known to be actually occupied by the 

 enemy. Under these conditions the artil- 

 lery quite naturally appealed to the avia- 

 tors, who, on account of the immobility 

 of the armies, were now less absorbed in 

 distant reconnoitering expeditions. 



Our brave pilots, who during the be- 

 ginning of hostilities had been carrying 

 the staff officers, now placed themselves 

 at the disposal of the artillery officers, 

 who set out to discover the hostile ob- 

 jectives by watching the regions of bat- 

 tery emplacements. The observation offi- 

 cer recorded on his map the position of 

 the batteries that had been surprised in 

 action during the course of his flight. 

 The landing was made on some field in 

 the immediate vicinity of the French bat- 

 teries, which, being informed in regard 

 to the position of the enemy, opened fire 

 in most cases according to the map — that 

 is to say, without observation of the hits. 



But it would have resulted in a far 

 greater efficiency had the aviator, after 

 discovering the objective, remained in the 

 air to observe the firing and report to the 

 battery the errors of its shots. This is 

 the problem of adjusting battery fire by 

 aerial observation (spotting), to the solu- 

 tion of which the artillery officers and 

 aviators are assiduously devoting them- 

 selves. 



One of the first methods had for its 

 basis the dropping of signal lights. Then 

 the aviator made use of certain evolu- 

 tions of his machine, indulging in per- 

 formances almost acrobatic to announce 

 the results of the shots. This crude 

 method was soon supplemented by the use 

 of radiotelegraphy. France enjoys the dis- 

 tinction of having been the first to make 

 use of radiotelegraphy on its airplanes. 



The enthusiasm evoked by the success 

 of these first spottings was only surpassed 

 by the chagrin of our enemies, who were 

 subjected to an accurate and murderous 

 fire from our batteries, while an airplane 



with the tricolored cockade was perform- 

 ing graceful evolutions over their heads. 

 It is only fair to add that within two 

 months after our first trials the Germans 

 had furnished their airplanes with radio 

 apparatus, so that we were able to verify, 

 at our own expense, the advantages of 

 this new method of directing artillery fire. 

 But for every new weapon there is a 

 corresponding defense, and for protec- 

 tion against the incursions of hostile air- 

 planes they are attacked by airplanes 

 armed with machine-guns, are fired upon 

 from the ground with special guns, and 

 certain curious stratagems are employed 

 which may be briefly described. 



PAKE BATTERIES TO DECEIVE SCOUT PLANES 



For the purpose of deceiving scout 

 planes in quest of targets, false battery 

 emplacements have been prepared and 

 provided with wooden guns. Seen from 

 above 4,500 feet, their appearance is the 

 same as that of the real batteries of which 

 they are a faithful copy. To complete the 

 illusion, as soon as a hostile plane passes 

 through the lines, the real batteries stop 

 firing, while the false ones are illuminated 

 by suitable artificial flashes, giving the ap- 

 pearance of a battery in action. This de- 

 ception is often very difficult to detect. 

 Both French and German gunners have 

 often fired at wooden batteries, while an 

 airplane perseveringly spotted the firing. 



These false batteries and the artificial 

 activity given them in the eyes of the avia- 

 tors could deceive only for a time, because 

 the aviators were not satisfied with sim- 

 ply observing them, but took photographs 

 of the field and were thus enabled to 

 study in detail, far from the excitement 

 of the front lines, the changes which the 

 defensive works of the enemy underwent 

 from week to week. 



By a careful study of these pictures 

 they learned to interpret them and thus 

 gave birth to a new branch of military 

 art, that of the interpretation of aerial 

 photographs. Without entering into the 

 details of this fruitful and fascinating 

 study, you can readily understand that 

 by means of lenses with a sufficiently long 

 focus an accurate image of the field can 

 be obtained, and that certain indications 

 on the photographs distinguish the real 

 batteries from the fictitious. 



