“It wasn’t a girl,” said Dorothea, as soon as she had wriggled back far enough to be able to lift her head without being seen from the top of the tower. “It was a boy in a kilt. The young chief of his clan looking far and wide from the battlements.”

      “Not far and wide,” said Roger. “He was looking straight at us.”

      “But what a place for a story,” said Dorothea. “Smugglers or Jacobites … or just villains with a prisoner in the tower. They might easily have a dungeon cut in the solid rock.”

      “Natives anyway,” said Titty. “We must get away from here as quick as we can.”

      “That dog’s stopped barking,” said Roger.

      As quickly as they could they were retreating out of the gap and down the cart track by which they had come. Already they could see down the steep slopes past the hill with the Pict-house to the creek, where the mast of the Sea Bear showed where all the older members of the crew were at work.

      “Let’s go back to my Pict-house,” said Roger. “And then, if we see natives pouring out of the gap, we can just slip down the hill, and get away.”

      “But we’re going to explore up the valley,” said Titty.

      “We’ll never find anything as good as the Pict-house,” said Roger.

      “Stop a minute and listen,” said Dorothea.

      There were no sounds of pursuit.

      “Well, if you won’t come back to my Pict-house,” said Roger, “what about creeping up to the gap again to have another look? I don’t believe that was a boy on the tower. It looked much more like a girl.”

      For a moment the others hesitated. Perhaps, if they had not known that they would be sailing next day, they would have waited and then crept up again to have another look at the native settlement beyond the ridge. But they knew that they had to be back at the ship before evening and that they would never see the place again.

      “Oh look here,” said Titty. “We can’t just give up exploring. We shan’t have another chance, not here anyway.”

      “And there’s Dick,” said Dorothea. “We said we’d pick him up on the way home.”

      So, though Roger looked regretfully up at the gap and back at that green mound on the top of the little hill, they presently turned west along the cart track leading towards the head of the valley. To the left, below them, they could see the two lochs, but no sign of Dick.

      “He’s made himself as invisible as he could,” said Dorothea. “He always does when he’s looking at birds.”

      Far ahead of them blue hills rose like a jagged wall, and above them to the right was the skyline of the Northern Rockies. Not one other human being was in sight.

      They walked on, following the cart track at first, but presently leaving it, because it kept on reminding them that they were not the first to discover the valley, and later coming back to the track again because they found it much slower work walking through heather and rocks and squashy patches of moss and peat. And anyhow, as Roger pointed out, the people who had built his Pict-house had discovered the valley pretty near the beginning of the world. Also, later inhabitants, cutting peats for winter fuel, had left deep trenches, some of them too wide to be jumped across. Good places to hide in, they agreed, but wasting a lot of time when you had to walk round them instead of going straight ahead.

      They had been walking for a long time. Deer, moving on the flats below them, had made them forget the native settlement on the other side of the ridge. Roger was leading the way. Dorothea was close behind him. Roger had said something about exploration being wasted on Dick, and Dorothea was explaining that there were more kinds of exploration than one and that birds, for Dick, were a part of exploration that really mattered, and that anyway Dick was as good an explorer as Roger. “Who got first to the North Pole?” Titty heard her say, and then, though Dorothea went on talking, and Roger too. Titty did not hear a word. She had suddenly got the queerest feeling that they were not alone.

      Down in the bottom, well behind them now, she knew that Dick was somewhere by the lochs. Further away still, she knew that Captain Flint and the four scrubbers were hard at work scraping and painting the Sea Bear before the tide could come up once more and float her off. So far as she could see there was no one else in the valley and the three explorers had the hillside to themselves. Yet, suddenly, she had the feeling that they were being watched, and watched from close at hand. She looked all round her, but could see nothing but rocky slopes and patches of heather and moss. There were no trees, no bushes. She shook herself, hurried on and tried to hear the end of Dot’s argument about different kinds of explorers. Of course there was nobody there, nobody but the three of them, walking the hillside in sunshine under a wide blue sky.

      A little later she had that feeling again. It was as if she were reading a book and someone had come up unseen and were reading it over her shoulder.

      “Dot!” she said.

      “Hullo,” said Dorothea. “Want a rest?”

      “Oh, not just yet,” said Roger.

      “What is it?” said Dorothea.

      “Nothing. Sorry,” said Titty. It was clear that neither of the others had felt what she had felt. And now, with the two of them stopping and looking back at her, she did not feel it herself.

      “More deer,” said Roger. “Dot, you’ve got my telescope.”

      Down below them on the wide flats in the bottom of the valley a herd of hinds were grazing like cattle.

      “They look as tame as anything,” said Roger.

      “They wouldn’t let us get near them,” said Dorothea.

      “Let’s try,” said Roger, “stalking …”

      “No, no,” said Titty. “We haven’t got half as far as we meant to do. If we go down now we won’t see anything. Let’s keep on and not go down till it’s time to start home.”

      “I’ve never seen them before except at the Zoo,” said Dorothea.

      “I expect they belong to those natives,” said Titty.

      “In winter,” said Dorothea, “the natives harness them like reindeer and fly in sledges over the snow.”

      “Bet they don’t,” said Roger. “Hullo!”

      From a patch of heather only a hundred yards ahead of them, a huge stag rose to his feet and was gone, in great leaps, down the slopes towards the head of the valley. All the deer grazing below stopped feeding and began to move.

      “Keep still,” said Titty.

      “I’m glad he didn’t charge this way,” said Roger. “But I didn’t think much of his horns. Did you?”

      “Perhaps they’ll grow,” said Dorothea.

      Presently the deer below stopped moving and began to graze once more.

      “Come on,” said Roger, and the explorers set out again.

      “They’ve seen us,” said Dorothea. “They’ll be off again in