"Yes, Miss Crane," Weston said, "I found a pretty suspicious circumstance to-day. Nothing less than a very small bottle, without cork or label, but smelling unmistakably of prussic acid."
"Where was it?" demanded Crane.
"Hidden in an old and unused paint-box of McClellan Thorpe's."
"Where was the paint-box?"
"'Way back, on a cupboard shelf. Pushed back, behind a pile of old books."
"Planted evidence," suggested Crane. "The real criminal put it there to incriminate Mr. Thorpe."
"Not a chance!" said Weston, smiling. "I've had that place watched too closely for that, sir! Nobody could get in to plant evidence, or to do anything else without being seen by my men. No, sir, that bottle in Mr. Thorpe's paint-box was put there by his own hand, and it will prove his undoing."
"But it's absurd!" flashed Julie. "Mr. Thorpe never killed his friend,—but if he had done so, he wouldn't be fool enough to leave such evidence around!"
"He couldn't help himself, Miss Crane. When he used the bottle that night, he had to secrete it somewhere, and since then he has been too closely watched to dare to take it from its hiding-place and dispose of it."
"But I don't see how he could have done it," Crane objected. "How could he persuade Blair to take a dose of poison?"