A big effort was made to escape detection by enemy aircraft. For the first time since the Egyptian Expeditionary Force took the field we had obtained mastery in the air. On the 8th and 15th October two enemy planes were shot down behind our lines, and the keenness of our airmen for combat made the German aviators extremely careful. They had been bold and resolute, taking their observations several thousand feet higher than our pilots, it is true, but neither anti-aircraft fire nor the presence of our machines in the air had up to this time deterred them. However, just at the moment when airwork was of extreme importance to the Turks, the German flying men, recognising that our pilots had new battle planes and were full of resource and daring, showed an unusual lack of enterprise, and we profited from their inactivity. The concentration of the force in the positions from which it was to attack Beersheba was to have taken seven days, but owing to the difficulties attending the development of water at Asluj and Khalasa the time was extended to ten days. During this period the uppermost thought of commanders was to conceal their movements. All marching was done at night and no move of any kind was permitted till nearly six o'clock in the evening, when enemy aircraft were usually at rest and the light was sufficiently dull to prevent the Fritzes seeing much if they had made an exceptionally late excursion. All the tents and temporary shelters which had been occupied for weeks were left standing. Cookhouses, horse lines, canteens, and so on were untouched, and one had an eerie feeling in passing at night through these untenanted camping grounds, deserted and lifeless, and a prey to the jackal and pariah dog. A vast area of many square miles which had held tens of thousands of troops and animals almost became a wilderness again, and the few natives hereabouts who had made large profits from the sale of eggs, fruit, and vegetables looked disconsolate and bewildered at the change, hoping and believing that the empty tents merely denoted a temporary absence. But the great majority of the Army never came that way again. When the infantry started on the march, divisions and brigades had allotted to them particular areas for their march routes, and all over that country, where scarcely a tree or native hut existed to make a landmark, there were dotted small arrow-pointed boards with the direction 'A road,' 'B road,' 'Z road,' as the case might be. Marching in the dark hours when a refreshing air succeeded the heat of the day, the troops halted as soon as a purple flush threw into high relief the southern end of the Judean hills, and they hid themselves in the wadis and broken ground; and on one unit vacating a bivouac area it was occupied by another, thus making the areas in which the troops rested as few as possible.