Facing in the same direction as the current they were now able to take a more comprehensive view of the gorge. "Where would you make your plunge if you wanted to swim across?" asked Bob. Lawrence looked along the bank. "There!" he said after a little, indicating a rock a few feet below and beyond them, that jutted out into the river. "Well, let’s go and take a look from there." They left the track, climbed on to the rock, and sat down there with their knees up, flinging pebbles aimlessly into the water. "I think you’re right," said Bob. "Allowing for the strength of the current it’s just about here that I should take the plunge. The oblique distance between this and the rope would make the diagonal--parallelogram of forces, you know." "I don’t suppose Nurla knows anything about that," said Lawrence with a smile. "But look here: don’t these bushes look as if they’d been disturbed recently?" He nodded his head towards some scrubby bushes at their right hand. "You’d think so, certainly," said Bob. "Still, we may be wrong. I remember old Colonel Fanshawe warning us against the danger of seeing what we wanted to see." After sitting a few minutes longer, keeping up the appearance of aimlessness by careless tossing of pebbles into the water, they rose and resumed their walk. But just at this moment Lawrence caught sight of a dark object among the bushes that grew sparsely on the hillside above the track, twenty yards away. At the distance, partially concealed by the foliage, the nature of the object was not apparent; but Lawrence clambered up by means of the bushes, and discovered a long coil of thin strong cord, lying between two inflated water-skins. He left them where they were, and returned to the track. "It’s clear as daylight," said Bob, when he had heard his report. "The fellow fastened the cord to the rock and held on to it when he took the water. He supported himself on the skins, and when he got to the other side, attached cord and skins to the dangling rope. When he came back, he hauled himself hand over hand against the stream, and pulled in the cord after him. That cord will, metaphorically speaking, hang the fellow, but he’s clever enough to have deserved a better fate." They returned slowly to the compound, well pleased with the result of their investigations.