It did not take us long to locate the source in a jumble of rocks where the mountain face rose up from another tumble of cracked stone forming a small talus at the rear of the bluff. It looked as if it was the result of a landslide, perhaps the same one that had caused Swallow’s bridge to fall, and maybe both had been the result of tremors in the mountains resulting from the Great White.

But when we had shifted enough stone, I was astonished to see that the water was dribbling from the mouth of an enormous pipe protruding from the mountain, half buried under rubble. ‘Why would the Beforetimers want such an enormous pipe to bring water here?’ Swallow wondered.

‘What purpose was there in any of the things done by the Beforetimers?’ Ahmedri asked softly.

Swallow drank the mouthful of water remaining in his bottle and filled it from the pipe, being careful not to splash his hands.

‘What are you doing?’ I asked.

He shrugged. ‘I want to find out if it is tainted. I’ll ask Darga to sniff it when we return. Speaking of which, we ought to head back now. It’s getting late and the wolves always come at sunset.’

He was right, though in fact Rheagor had not mentioned sunset this time. The sun set before we were all the way down, but the moon had risen and the clouds had frayed enough that there was plenty of light to see by. But Swallow had been right about the climb down being worse in its own way than the ascent. It was utterly unnerving to go backwards, feeling for footholds and climbing slowly down the rope. Whenever I made the mistake of looking down for a foothold, my eyes were drawn to the black abyss, even though our descent was above the talus. I could hardly bear to think about Ahmedri, who was untying the ropes before climbing down.