"This is incomprehensible to me. After reading that Texan's letter, I was so assured that however vengeful he might be, still he was an honorable man, that I felt positive he would keep his word, and that this man would be safe at the expiration of the note."
"You were entirely right in your estimate of the Texan's character, Mr. Barnes. Your fatal error was in regard to the expiration of the note."
"Why, the thirty days expired at noon to-day."
"Very true. But you have overlooked the usual three days' grace!"
"The devil."
"Just so; the devil,—in this instance the devil being the Texan. Ordinarily the extra three days is an extension demanded by the maker of the note, but in this instance it has been utilized by the deviser of the scheme, who, knowing that his man would be on guard during the thirty days, misled him by a promise of safety thereafter. But he did more than that."
"What do you mean?"
"Why, how has he accomplished his purpose? How has he killed this man up here in a locked room, which has no window through which a bullet might be fired?"
"I do not know; that is another puzzle to be solved."
"I have already solved it. The promissory note is the vehicle of his vengeance,—the means by which the opportunity was obtained, and the means by which the end has been consummated. You will recall that Odell told you that the Texan promised that if he should live beyond the limitation of the note it would be returned so that he might burn it, and he might then consider the matter terminated. These were very suggestive words, and have wrought this man ruin. Evidently soon after he reached this hotel, feeling that at last he had escaped his threatened doom, an envelope was sent up to him, which contained the so-called promissory note. It being too dark in here to read, he lighted his gas. The reception of this paper caused him satisfaction because it seemed to show that his adversary was keeping faith. It had been suggested to him that he might 'burn' the note, and so 'terminate' the affair. Therefore he set fire to the paper, which evidently had been charged with an explosive substance. The explosion not only stunned if it did not kill the man, but it extinguished the gas, leaving the jet open, so that if not destroyed by the explosive he certainly must have been asphyxiated by the escaping gas. Here on the floor is a bit of the paper, and we can still see a few of the words which we know were contained in the promissory note. Then there is the gas turned on, while it is still daylight without. Am I right?"