“Tom isn’t guilty, I am sure of that.”

“And Raymond Case is equally certain that Miss Langmore isn’t guilty.”

“He is the young man who came here and engaged you?”

“Yes.”

“Is he engaged to her?”

“Yes.”

“Then, of course, he thinks her innocent.”

“I think her innocent myself.”

“Do you think Tom is guilty?”

At this direct question Adam Adams winced.  He saw before him a disagreeable duty which must be performed.

“I see I must give you the facts, Letty.  But I will do so on one condition only, and that is, that you keep what I have to say to yourself—­considering them as office secrets.”

“Very well, Uncle Adam, I’ll promise,” she answered, with a pale face upturned to him.  He bent down and kissed her on the forehead.  Then he locked the office door, sat down in an armchair and let her sit on his lap, just as she had done since childhood.

His recital took the best part of an hour, and he gave all the particulars of his interview with Cephas Carboy and with Doctor Calkey, and told of the finding of the bit of paper with the address of the drug firm on it, and of the strange Chinese poison.  At the mention of the fatal drug she drew a sharp breath.

“I—­I—­” she began, and stopped short.

“Do you know anything of that drug, Letty?  Perhaps he spoke to you about it?”

“He did, once, when we were speaking of poisons.  He said he was glad his firm had decided not to handle it, for it was too dangerous.  It has a power that most folks do not know about.”

“The power to kill people, I suppose.”

“No, not that.  He said it was a fatal drug, but more than that, he said it had a strange power, according to the Chinese chemists who manufactured it.  That power was, if it was used on a person and did not kill it would, in a few days or a week, make that person mad.”

“Humph!  Worse and worse!  Such a drug should be banished by law.  But to go on with my story, if you must hear the whole of it.  I am fairly certain it was that drug which was used to kill Mr. and Mrs. Langmore.”

“But Tom did not use it,” she insisted.  “Somebody else must have gotten the drug from him or from his traveling sample case.”

“That is possible.  Now there is another side to this case, which I cannot understand at all.”  And then he told of the counterfeit bank bills.

“Counterfeits!” she exclaimed, and the color began to leave her face once more.  “What kind of bills were they, Uncle Adam?”

“They were one hundred dollar bills, on the Excelsior National Bank of New York City.”

She gave a gasp and clenched her little hands to control herself.  He could not help but notice her increased agitation.

“What is it, Letty?  Do you know—­”

“Oh, Uncle Adam, do not ask me,” she gasped.  “I—­I—­there is some mistake—­Tom did not—­” she failed to go on and looked at the detective hopelessly.