"But, Mr. Cumshaw," Moira protested, "do you think you feel well enough?"
"Miss Drummond," he answered, "I've got pains all down my neck, and my head's humming like a hive of bees, and I've got incipient rheumatics in every joint in my body from lying all night on the damp ground. It's bad enough to have all that wrong with me, without being compelled to spend another day in idleness. No, if I get to work at once I'll feel much better. Work, you know, is a good soporific."
"I suppose you know best," she conceded, a little doubtfully.
"I've been thinking things over," I remarked as we made our way back to the site of the hut, "and it's just struck me that something I once heard Bryce say might have some bearing on the matter. The night those chaps burgled us he said, 'They're up a gum-tree when they should be under one.' I'm not so sure of the exact words now, but that's the substance of them anyway."
"But," Cumshaw objected, "he didn't know as much about the Valley then as we do now."
"Quite so," I said. "I never thought he really meant anything by what he said, but that remark's been running through my head. It seems to me that everyone right through has been obsessed by the idea of the tree, and now that it's disappeared we're at a loose end. Everybody, from your father and Bradby down to Bryce and ourselves, has taken it for granted that a tree's vital to the solution."
"Isn't it?" Cumshaw queried quickly.
I shook my head. "Not in the least," I said. "If the tree was absolutely necessary it'd mean that we'd have to wait until 3rd or 4th of December, the day on which Bradby buried the treasure, and the only day of the year on which the sun, the tree and the threshold of the hut would be in an exact line. Bryce's idea of having to wait three months must have been conceived in the belief that the 3rd or 4th June would answer equally well. It might, but I'm not so sure about it. I guess there'd be a lot of difference in the declination of the sun. But now the tree's gone we're left without that seemingly necessary leading mark."
"What are we going to do about it?" Cumshaw demanded.
"We can't give up after having gone so far," said Moira.