"We must get sleep," declared Uncle Brian. "It is absolutely essential at this stage of our journey. Later on we may not have the opportunity. We'll keep watch-and-watch. As an extra precaution, I think we'll fire this grass." "Don't forget we've gallons and gallons of petrol on the boat," Peter reminded him. "By Jove, yes," agreed his uncle. "All right, Peter, you push off in the boat until the grass has burned itself out. It won't be very long." Peter took to the oars and rowed the "orange-box" well out into the stream. Brian Strong struck a match and applied it to the sun-dried grass. The result exceeded his expectations. The flames literally ran, throwing orange-coloured tongues of fire fifty feet in the air. The heat was terrific. Although he retreated to the water's edge, with twenty yards of sand between him and the edge of the conflagration, Brian could barely stand his ground. It was a nasty predicament. To shout to Peter to bring the boat in would probably result in the petrol exploding, since the sparks were flying to wind'ard, which was what Brian Strong had thought he had guarded against. To attempt to swim off was equally hazardous, owing to the presence of the deadly electric eels. The flames died down almost as quickly as they had shot up, although on the furthermost side of the island the fire was burning even more fiercely than before. In a quarter of an hour the place was thoroughly cleared of animal and vegetable life, the bare rock showing through the diminishing wreaths of smoke from the smouldering timber. "We've cleared out the mosquitoes at all events," declared Peter, as he rejoined his uncle and once more made the boat secure. "S'pose this packet will be all right in case of a shift of wind?" "We're sheltered," declared Uncle Brian. "The only wind that can hurt us is a southerly one. That's very rare in this district; it's the Norther that plays up Old Harry.... Right-o, you turn in. I'll keep watch till midnight; that's another five hours. We'll make a start at dawn." Clearing away a space amidships, Peter lay down in the boat and was soon sound asleep, his strange surroundings notwithstanding. In fact, it seemed to him that he had only just dropped off when his uncle roused him. "Half-past twelve, Peter," he announced. Peter had been used to keeping Middle Watch, but, if the truth be told, he would have infinitely preferred the bridge of a British cruiser at 1 a.m. to the stretch of sand on the edge of the fire-devastated island. It was not pitch-dark. A dank mist hung over the river, blotting out the tree-clad banks on either hand. Overhead, the stars shone dimly through the drifting pall of vapour. The air reeked with noxious odours of decaying vegetation mingled with the sickly smell from the burnt grass.