On July 10th last, Rheinold Boehm rose from the Johannisthal Aërodrome at 5.54 a.m. on an Albatross biplane of military type, furnished with a Mercèdes motor of 75 h.p. He flew round about Berlin. During the night-time the aërial lighthouses indicated to him his whereabouts. He did not touch the earth till 6.12 p.m., having been in the air for twenty-four hours and twelve minutes. It is curious to note in what regular progress the records of duration had been won this year. On February 4th the German Langer flew continuously for 14 hours 7 minutes. On February 7th the German Langer had flown for 16 hours 20 minutes. On April 8th the Frenchman Poulet had flown for 16 hours 28 minutes. On June 22nd and 23rd the German Basser wrested the record away from Poulet, and accomplished 18 hours 12 minutes. Then the German Landmann on June 27th and 28th beat his countryman with the record of 21 hours 50 minutes. Then came the final exploit of Boehm, which has been recorded above. CHAPTER IX THE FIRST USE OF THE AËROPLANE IN WAR--TRIPOLI--THE BALKANS Manœuvres in peace were the first practical test of the value of aëroplanes in war. The French proved their efficiency in their manœuvres in Picardy as long ago as 1910. The result of their use was a surprise for the military authorities themselves. Before the test it had been considered that an observer in an airship which could hover over the lines of the enemy or over a fortification would have a good chance of being able to bring back to headquarters useful details of what they had seen; but it had been thought by many military experts that the aëroplanist from his forced, rapid movement would not be able to form a mental picture of what actually passed his eyes, that if the retina had recorded the fleeting image on the brain, there would be confusion. The success of the aviator was an example of the truism that experience often does not coincide with preconceived opinion, for the reason that some unknown factor exists, and is only brought to light by the special circumstances of the case. Of all people, the aviator is one who constantly practises sharpness and concentration of sense; his eye and brain have a perpetual habit of harmonious and close-bound working; time to him has an enhanced value; none, like he, has ever learnt the exigencies of the minutes. His whole system becomes acclimatised to the constant maintenance of the equilibrium of his powers, for he has realised that for any negligence he will pay the death penalty. Is it wonder then that the glance of the practised aviator over the far-stretching regions beneath him becomes super-sight? So is it that the best aërial observer is often one who combines in himself the varied occupation of engineer, pilot, and scout, and who in his swift machine, arrow-like, darts above the enemy.