All's Well was only waiting for Véronique's permission. He dashed off in the direction of the grassy sward that led to the dolmen; and he stopped half way. Véronique came up with him. He turned to the right and took a path which brought them to a huddle of ruins near the edge of the cliffs. Then he stopped again.
"Is it here?" asked Véronique.
The dog lay down flat. In front of him, at the foot of two blocks of stones leaning against each other and covered with the same growth of ivy, was a tangle of brambles with under it a little passage like the entrance to a rabbit-warren. All's Well slipped in, disappeared and then returned in search of Véronique, who had to go back to the Priory and fetch a bill-hook to cut down the brambles.
She managed in half an hour to uncover the top step of a staircase, which she descended, feeling her way and preceded by All's Well, and which took her to a long tunnel, cut in the body of the rock and lighted on the left by little openings. She raised herself on tip-toe and saw that these openings overlooked the sea.
She walked on the level for ten minutes and then went down some more steps. The tunnel grew narrower. The openings, which all looked towards the sky, no doubt so as not to be seen from below, now gave light from both the right and the left. Véronique began to understand how All's Well was able to communicate with the other part of the island. The tunnel followed the narrow strip of cliff which joined the Priory estate to Sarek. The waves lapped the rocks on either side.
They next climbed by steps under the knoll of the Great Oak. Two tunnels opened at the top. All's Well chose the one on the left, which continued to skirt the sea.
Then on the right there were two more passages, both quite dark. The island appeared to be riddled in this way with invisible communications; and Véronique felt something clutch at her heart as she reflected that she was making for the part which the sisters Archignat had described as the enemy's subterranean domains, under the Black Heath.
All's Well trotted in front of her, turning round from time to time to see if she was following.
"Yes, yes, dear, I'm coming," she whispered, "and I am not a bit afraid: I am sure that you are leading me to a friend . . . a friend who has taken shelter down here. But why has he not left his shelter? Why did you not show him the way?"
The passage had been chipped smooth throughout, with a rounded ceiling and a very dry granite floor, which was amply ventilated by the openings. There was not a mark, not a scratch of any kind on the walls. Sometimes the point of a black flint projected.