“If I give him a chance or don’t kill him.”

“You will ignore it, and——”

“And accept his challenge—surely!” Nick cut in. “Wait one moment. I want to question Burton.”

They had remained near the office inclosure, to which he now turned and called the clerk, asking quietly:

“Who brought this letter, Mr. Burton? I see it is not stamped.”

Burton laughed a bit oddly and shook his head.

“I don’t know, Mr. Blaisdell,” he replied. “I found it on the cigar case. I was somewhat mystified when I saw it, for I had sold two men some cigars only a moment before, and the letter was not there.”

“One of them left it there, perhaps,” Nick suggested, intending to get a description of the men, in that case.

“Impossible.” Burton spoke decidedly. “They walked away before I closed the show case, and I saw them leaving the house.”

“Did you see any one else near the show case?”