six o'clock
When he left Constantinople his anemometer indicated a velocity of eighteen miles in the south-west wind , which , as he was steering south-east , was partly in his favour . One of the disabilities which he , in common with all airmen , suffered , was the impossibility of ascertaining the velocity of the wind when he was fairly afloat . He had to make allowance for it by sheer guesswork , unless he was prepared to slow down or even to alight . He had reckoned that , even with the slight assistance of the wind , he could hardly hope to reach the head of the Persian Gulf before six o'clock , which would be past nine by the sun ; but he thought he might reasonably expect to reach the Euphrates before sunset ; and since the map assured him that that river ran a fairly direct course to the Gulf , he might follow it without much difficulty if the night proved clear , and so assure himself that he was not going astray . The country over which he was now flying was hilly , and he kept at a fairly high altitude . The map showed him that the great Taurus range lay between him and the eastern extremity of the Mediterranean . Within an hour and a half after leaving Constantinople he came in sight of its huge bleak masses stretching away to right and left , but still a hundred miles or more distant , although , on the right , spurs of the Cilician part of the range jutted out much nearer to him .