National Geographic : 1918 Jan
THE NATIONAL GEOGRAPHIC MAGAZINE 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. FAKE 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.