During the battle of the Aisne, the wireless machines were few in number and other methods of signalling were mostly in use. On the 15th of September Captain L. E. O. Charlton fired Very lights over enemy guns previously observed. On the 24th of September 'Lieutenant Allen and two others with aeroplanes indicated targets and observed fire, communication being by flash signals'. Sometimes the pilots returned and landed to report on gun positions. But when once the gunners had profited by the superior accuracy and speed of report by wireless, they were hungry for more machines. On the 23rd of September the commander of the Second Corps telegraphed to General Headquarters: 'I hope that you will be able to spare the wireless aeroplane and receiving set to Third Division again to-morrow. The results were so good yesterday that it seems a pity not to keep it with the Division, which has got accustomed to its uses and is in a position to benefit even more largely by the experience gained.' The answer was that the machine had been damaged by anti-aircraft fire, but would be ready again shortly. A wireless aeroplane was as popular as an opera-singer, and the headquarters wireless section soon developed into No. 9 Squadron of the Royal Flying Corps. The attitude of the gunners may be well seen in an entry made in the war diary of No. 3 Siege Battery, dated the 23rd of January 1915--'Airman' (Captain Cherry) 'reported for co-operation (lamp only, alas!).' The photography was a mere beginning. On the 15th of September Lieutenant G. F. Pretyman took five photographs of the enemy positions; these were developed later on the ground, and were the forerunners of that immense photographic map of the western front in thousands of sections, constantly renewed and corrected, which played so great a part in the later stages of the war. Some other experiments had no later history. Steel darts called 'flechettes', about five inches long and three-eighths of an inch in diameter, were dropped over enemy horse-lines and troops by No. 3 Squadron. A canister holding about 250 of these darts was fixed under the fuselage; by the pulling of a wire the bottom of the tin was opened and the darts were released. To do any harm these darts had to score a direct hit on some living object, so that a whole canister of them was probably a less formidable weapon than a bomb. Even on a battle-field life is sparsely distributed on the ground.