The Poisoned Pen | Page 8

As he met Craig's fixed glare he knew there was no hope. Slowly, as if the words were being wrung from him syllable by syllable, he said in a muffled voice:
"No, I perjured myself. I was served in that suit. But - "
"And you swore falsely before Kimmel that you were not?" persisted Kennedy.
"Yes," he murmured. "But - "
"And you are prepared now to make another affidavit to that effect?"
"Yes," he replied. "If - "
"No buts or ifs, Thurston," cried Kennedy sarcastically. "What did you make that affidavit for? What is your story?"
"Kimmel sent for me. I did not go to him. He offered to pay my debts if I would swear to such a statement. I did not ask why or for whom. I swore to it and gave him a list of my creditors. I waited until they were paid. Then my conscience - " I could not help revolting at the thought of conscience in such a wretch, and the word itself seemed to stick in his throat as he went on and saw how feeble an impression he was making on us - " my conscience began to trouble me. I determined to see Vera, tell her all, and find out whether it was she who wanted this statement. I saw her. When at last I told her, she scorned me. I can confirm that, for as I left a man entered. I now knew how grossly I had sinned, in listening to Mose Kimmel. I fled. I disappeared in Maine. I travelled. Every day my money grew less. At last I was overtaken, captured, and brought back here."
He stopped and sank wretchedly down in a chair and covered his face with his hands.
"A likely story," muttered Leland in my ear.
Kennedy was working quickly. Motioning the officers to be seated by Thurston, he uncovered a jar which he had placed on the table. The colour had now appeared in Alma's cheeks, as if hope had again sprung in her heart, and I fancied that Halsey Post saw his claim on her favour declining correspondingly.
"I want you to examine the letters in this case with me," continued Kennedy. "Take the letter which I read from Miss Lytton, which was found following the strange disappearance of the note from Thurston."
He dipped a pen into a little bottle, and wrote on a piece of paper:
What is your opinion about Cross's Headache Cure? Would you recommend it for a nervous headache?
BURGESS THURSTON, c/o Mrs. S. BONCOUR.
Craig held up the writing so that we could all see that he had written what Dixon declared Thurston wrote in the note that had disappeared. Then he dipped another pen into a second bottle, and for some time he scrawled on another sheet of paper. He held it up, but it was still perfectly blank.
"Now," he added, "I am going to give a little demonstration which I expect to be successful only in a measure. Here in the open sunshine by this window I am going to place these two sheets of paper side by side. It will take longer than I care to wait to make my demonstration complete, but I can do enough to convince you."
For a quarter of an hour we sat in silence, wondering what he would do next. At last he beckoned us over to the window. As we approached he said, "On sheet number one I have written with quinoline; on sheet number two I wrote with a solution of nitrate of silver."
We bent over. The writing signed "Thurston" on sheet number one was faint, almost imperceptible, but on paper number two, in black letters, appeared what Kennedy had written: " Dear Harris: Since we agreed to disagree we have at least been good friends."
"It is like the start of the substituted letter, and the other is like the missing note," gasped Leland in a daze.
"Yes," said Kennedy quickly. "Leland, no one entered your office. No one stole the Thurston note. No one substituted the Lytton letter. According to your own story, you took them out of the safe and left them in the sunlight all day. The process that had been started earlier in ordinary light, slowly, was now quickly completed. In other words, there was writing which would soon fade away on one side of the paper and writing which was invisible but would soon appear on the other.
"For instance, quinoline rapidly disappears in sunlight. Starch with a slight trace of iodine writes a light blue, which disappears in air. It was something like that used in the Thurston letter. Then, too, silver nitrate dissolved in ammonia gradually turns black as it is acted on by light and air. Or magenta treated with a bleaching-agent in just sufficient quantity to decolourise it is invisible when used