He took his bearings. The aeroplane was facing down-stream. He would have to rise many hundreds of feet before it would be safe to turn. "They may fire at you and hit you before you’re out of range," said Lawrence. "I must take my chance. Of course they’ll see me against the sky if they look up; but it will take them a few seconds at any rate to collect themselves, and I shall be going so fast that I fancy they won’t hit me if they try. Here: take your rifle and cartridges. You’ll keep strict watch? Look for me in the morning. So long!" He started the engine: Lawrence stood clear, and the aeroplane darted forward obliquely towards the river. In a second or two it was completely lost to sight, so dense had the darkness become. But in a few seconds more it could be seen like a shadow against the sky, a quarter of a mile down the river and several hundred feet above. There were faint shouts in the distance. The enemy’s attention must have been attracted, first by the hum, then by the sight of the strange machine as it soared higher and higher. But there was no sound of firing, and Lawrence breathed freely when he knew that his brother had escaped this first danger. A few minutes later he saw the aeroplane at a great height, sailing rapidly towards the mine. On running off, Bob adjusted his elevator for the steepest possible ascent in a direct line; the gorge was too narrow to allow of a spiral ascent. He felt that he was starting on a race with the darkness. He had never attempted a flight by night in these regions, and he hoped by rising high to use the last radiance of sunset in shaping his course. Within about half an hour he should arrive at the mine. But he was a good deal more concerned than he had allowed Lawrence to see, at the problem which would face him at the end of his flight. The situation of the mine would be revealed by the camp fires of the labourers on the right bank, and the lights about the various outhouses on the left. But there were no lights on the landing platform beyond, and this, together with all the lower part of the gorge, was already blotted out by the darkness. It would be impossible, however gently he should glide down, to hit the exact position of the platform; and to attempt a landing at random would be madness. Bob felt much worried as he flew on in the fading light, with an immense black abyss beneath him. The approach of the aeroplane would certainly be heard at the mine, but probably no one would be quick-witted enough to understand his difficulty. It might never occur to them that the darkness would render a landing impossible. Bob suspected that not even Ditta Lal, B.A. of Calcutta University though he was, would be alive to the position. Puzzle as he might, he could not hit upon any solution of the problem, and at length ceased to think about it, hoping that chance or some lucky inspiration, some circumstance that he had not taken into account, would point the way in due time.