"You certainly have; and I shall manage the rest—at least I hope so. On the wall just opposite the cupboard in the museum—the one which appears here in the photograph—there is, right enough, a mirror, a tolerably large one, and it is in that mirror that the photograph was taken."
"But then, the person who took it must have stood right beside Evelina, and he could not very well have avoided being included in the photograph." It was Clara who made this remark.
"You are quite right, Mrs. Viller; but he stood so much to one side that he did not come within the frame of the mirror. To prevent the frame from showing in the photograph, he has clipped it on both sides. That is why the picture is so narrow."
"This is all very well," I felt compelled to remark, "but there is one thing which upsets the whole of your fine theory. Is it at all likely that Evelina would allow any one to stand beside her and photograph her in the mirror, while she was about to steal a diamond, or, more correctly, would she choose the moment to steal the diamond while she was being photographed?"
"Yes, it was just that point which I found to be the most difficult, a little while ago, when I was building up my theory, so to speak; but I have happily solved that question, and the solution opens up a still larger vista to us."
"When you were building up your theory, you say? Do you mean those seconds a little while ago, when you stood with staring eyes, and muttering something about eating dust?"
"It is possible that I behaved rather strangely," laughed Monk; "and I haven't an idea how long I was away from this world. But even if it was for only a few seconds, they were, at any rate, more than sufficient to reveal to me what had really taken place behind the scenes, and which I, until now, have been quite deceived about. Just listen! If you remember my description of the little house in Frick's garden, of which the museum was a part, you will remember that from the museum there is a door leading to the fire-proof room. This door is just at the side of the cupboard which we have referred to so often. The only way in which one could, by aid of the mirror, photograph a person without being noticed in front of the cupboard, would be by standing inside the fire-proof room, leaving the door of the museum ajar."
"Do you mean that the Englishman had been inside old Frick's fire-proof room? The door of that surely wouldn't be open?"
"No, it is a strong iron door of which old Frick had the key; but for a clever man, whose time was his own, it would not be a difficult matter to procure a false key. You remember that Howell had had the entrée to the museum whenever he liked, for many months."
"But what business had the Englishman in there? He must have been a great scoundrel; and there is no reason why he should not help himself to what he could find. But perhaps there was not much cash there, and besides, you have not said anything about old Frick being robbed of any."