"I can explain!"
"That is why I sent for you," said Mr. Mitchel.
"The note was my own," said the girl, speaking rapidly, "but after the disappearance of the other, I was afraid to have it in my room lest it be found, and seem to inculpate me. I only received it a few days before my dear uncle died. He told me that his brother William had sent it as a present to my mother upon her marriage, but as he had doubted the good intentions of my father, he had kept the matter a secret. As both my parents died, he had held the note in trust for me. He did not invest it, because he thought that his own fortune would be an ample legacy to leave me. A short time before he died, I passed my twenty-first birthday, and he gave me the note. That is the whole truth."
"To which I can testify," interjected Mr. Lumley. "And I may now add that Miss Hetheridge had not only promised to be my wife, but she offered me the use of her money to buy the partnership, which to Mr. Barnes seemed such a suspicious act."
"I have only to explain then," continued Mr. Mitchel, "how it was that I decided that Miss Hetheridge was not the thief. This morning I found heavy frost on the window-panes. Upon one, however, I noticed a circular, transparent spot, where the pattern of the frosting had been obliterated. Instantly I comprehended what had occurred. The thief, the real thief, had come in the night, or rather in the morning, for I know almost the hour. He stood upon the shed outside, and melted the frost by breathing upon the pane, with his mouth close to the glass. Thus making a peep-hole, he must have seen me asleep on the sofa, and so knew that it would be useless for him to attempt an entrance. As the person who did this trick stood upon the shed, I had but to measure the distance from the shed to his peep-hole to be able to guess his height, which I estimated to be more than six feet. Next, there was some very interesting evidence in the frost on the tin roof. The marks made by the man's feet, or his heels rather, for the frost was so light that only the impressions of the nails in the heels would show. My own made complete little horseshoe-shaped marks composed of dots. But those of my predecessor were scarcely more than half a curve, which proved that he walks on the side of his foot, thus slightly lifting the opposite side from the ground, or roof, as it was in this instance. This much decided me that Miss Hetheridge was not the thief, and I returned her bank-note to the place where she had hidden it. Then I sat at the table where the will was read, and studied the situation. The easiest way to hide the note quickly seemed to be to slip it into the Bible which stood on the table. Therefore I was not surprised when I found the bank-note which I have here."
He drew forth the bank-note from his pocket and handed it to Mr. Van Rawlston, who asked:
"But why, then, did you try to buy the Bible?"
"I had no idea of doing so. You forget that I had not seen Mr. Lumley. He, too, might have been six feet high, and he, too, might have had the habit of walking on the side of his heel, as I quickly observed that Mr. Eggleston does. With only one of the men before me I decided to run up the price of the Bible, knowing that if he were guilty he would bid over me. Mr. Eggleston followed my lead, and I was almost sure of his guilt, when he made the remark that he was buying a family relic. It was a possible truth, and I was obliged to go on bidding, to see how anxious he was to possess the volume. Then, as I said awhile ago, Mr. Lumley arrived in the nick of time. One glance at his short stature, and I was ready to let the Bible go."
"You said you could almost tell the hour at which this man peeped through the window," said Mr. Barnes.
"Ah, I see! You wish me to teach you tricks in your own trade, eh? Well, frost forms on a window-pane when the thermometer is near or below thirty-two. On the wall here I found a recording thermometer, which discloses the fact that at three o'clock this morning the temperature was as high as forty-five, while at four it was below thirty. Frost began to form between those hours. At five it was so cold, twenty degrees, that I awoke. Our man must have come between half-past four and five. Had he come before then, his peep-hole would have been fully covered again with frost, whereas it was but thinly iced over, the mere freezing of the water of the melted frost, there being no design, or pattern, as there was over every other part of the window-pane. So I may offer you a new version of an old saw, and say that, 'Frost shows which way a thief goes.'"