She gave his hand a sudden squeeze and turned towards the house.
“That was a bit of luck, meeting her out here!” murmured Alec raptly to himself as he watched her go. Wherein he was not altogether correct in his statement of fact; for as the lady had come into the garden for that express purpose, the subsequent meeting might be said to be due rather to good generalship than good luck.
It was therefore a remarkably jubilant Watson who returned blithely to the library to find his Sherlock sitting solemnly in the chair before the big writing table and staring hard at the chimney-piece.
In spite of himself he shivered slightly. “Ugh, you ghoulish brute!” he exclaimed.
Roger looked at him abstractedly. “What’s up?”
“Well, I can’t say that I should like to sit in that particular chair just yet awhile.”
“I’m glad you’ve come back,” Roger said, rising slowly to his feet. “I’ve just had a pretty curious idea, and I’m going to test it. The chances are several million to one against it coming off, but if it does——! Well, I don’t know what the devil we’re going to do!”
He had spoken so seriously that Alec gaped at him in surprise. “Good Lord, what’s up now?” he asked.
“Well, I won’t say in so many words,” Roger replied slowly, “because it’s really too fantastic. But it’s to do with the breaking of that second vase. You remember I said that in order for it to have smashed like that it must have been struck extraordinarily hard by some mysterious object. It’s just occurred to me what that object might possibly have been.”
He walked across to where the chair was still standing in front of the fireplace and stepped up on to it. Then, with a glance towards the chair he had just left, he began to examine the woodwork at the back of the chimney-piece. Alec watched him in silence. Suddenly he bent forward with close attention and prodded a finger at the panel; and Alec noticed that his face had gone very pale.