Only for a moment was Lawrence's attention diverted from his quest. Hitherto he had fixed his eyes from a rapidly diminishing distance upon the spot where his uncle had fallen, and the river beyond. Now he had passed the spot itself, and in a few seconds covered the whole distance down which, even allowing for the speed of the current, the body could have been carried. There was no sign of it, and Lawrence felt with horror and despair that the shot had been only too well aimed--that Mr. Appleton had been killed outright, or so grievously wounded as to be unable to keep himself afloat. He could not endure the suspense and uncertainty.
"I am going in," he cried. "Come back for me."
To make a clean dive from the narrow seat of an aeroplane flying at the rate of thirty miles an hour was impossible. It was a dangerous feat to attempt at all, but Lawrence did not think of that. He fell rather than plunged, at the imminent risk of striking a half-submerged rock in mid-stream. The shock of hitting the water after a haphazard fall of thirty feet was so great that for a time, even after he had risen to the surface, he was too much dazed to be able to distinguish his surroundings. With the instinct of a practised swimmer he trod water until his senses returned to him. Then he saw that he was far below the ruined bridge, and being rapidly carried down-stream. The aeroplane was out of sight. Neither man nor beast was visible on either bank. The Kalmucks must have clambered up the bank and taken to flight. He realized that if his uncle was still in the river he must have overtaken him before the dive was made. It was necessary to husband his strength, and either try to swim against the stream, or make his way to some rock on one side or the other, whence he could watch the current as it flowed past him.
He turned, and for some time breasted the stream until he descried a rocky shelf at the base of the right bank which would prove at once a resting place and a convenient watch post. Nearly exhausted, he dragged himself on to it, and crouched there, intent upon every billow and eddy of the swollen river. Fed by the mountain snows, it flowed on with turbulent tide. The water was bitterly cold, and Lawrence shivered as he waited there minute after minute, hoping, yet dreading, to see his uncle's form rolling past.
Presently he heard the hum of the returning aeroplane. Bob shouted as he sped by, but what he said was indistinguishable. Lawrence felt more and more despairing until with a gleam of hope he wondered whether his uncle had swum to one bank or the other and climbed to safety. He looked at the bank behind him. It was steep, almost perpendicular, but marked by fissures that promised to give him foothold. With teeth chattering and limbs trembling with cold he essayed to clamber up. At another time he would have found the feat easy enough: now he was amazed at the tax it put upon him. Every now and then he stopped, clung on with his hands, and turned his head to glance again at the stream. At last, on gaining the top, he looked along the track in both directions. Nobody was in sight. The aeroplane had again disappeared from view. Hesitating a moment he began to walk up the track. A new fear assailed him: what if the aeroplane had met with an accident! What if the engine had failed, or the pilot had been too venturesome, and in attempting to wheel in too narrow a space had crashed against the rock! Shivering as much from anxiety as from cold, he felt a glow of extravagant delight when he heard a cheery shout, and Bob came hasting towards him from round the corner of a jutting rock.
"Any sign of him?" asked Bob anxiously as he met his brother.
"No. What can have become of him?"
"I fear the worst: but even if--if he is drowned he must come up some time. We had better walk up and down for a bit."
"Where's the machine?"
"A few yards above the bridge. It was a risky thing, coming down there, but I thought I'd venture, and luckily didn't come to grief."