The correspondent of the _Bourse Gazette_ goes on to remark that the history of the struggle for mastery in the air is very instructive. ‘At the beginning of the war the supremacy in aviation undoubtedly belonged to the British and the French. But during the first year of the war the Germans, availing themselves of their superior industrial organization, went ahead of the Allies. For a brief period German aviation surpassed not only the British and French aviation separately, but both combined. That period coincides with the appearance of the Fokkers and the activity of Immelmann and other prominent German pilots.’ But the Germans, as we have seen, could not maintain their superiority. Towards the end of the second year, the supremacy passed to the Allies once more. By the quantity and quality of their machines, as well as by the quantity and quality of their pilots, the British and French now so much surpass the Germans that at present one can speak of the absolute superiority of the Allied aviators. ‘The Allied aviation,’ the writer in point continues, ‘is divided into three separate branches or three kinds of fighting—the attacking battle-squadron, something like aerial cavalry; the scouts, rather like aerial infantry; and a division of aerial photographers. The pilots of the aerial battle-squadron are the real fighters of the air. Most of them are young. And the lives of all of them are filled with unprecedented adventures.’ Of all branches of aviation, however, the most important in the estimate of the writer of the article is that of photographing from an aeroplane: ‘Before the bombardment of any enemy position, the head quarters make a detailed map, drawn up from photographs taken from the aeroplanes. Then, while the bombardment is in progress, the aviators continue to take photographs of the position at fixed intervals. The bombardment continues until the photographs taken by the aviators show them all the _points d’appui_ of the positions have been demolished. I saw these photographs and the maps of the German positions prepared from them. The making of these photographic maps is one of the greatest technical miracles of the present war. But its realization demands indomitable courage and sang-froid. Photographing the enemy positions is at once the most ingenious and the most dangerous of aerial operations. The aviator-photographer having risen to a great height above the enemy position, settles his aeroplane almost vertically above the position he is going to photograph. Descending a certain distance, he arranges his camera, takes his photograph of the German defences, and at once climbs up at top speed in order to regain his own lines. One can imagine with what a fire the Germans meet their uninvited visitor. All the while his dizzy manœuvres over the German positions are going on, he has to face the fire of anti-aircraft guns, machine-guns, and rifles.