He could see through the doorway to the window that opened on the alleyway, or, rather, just glimpse the top of the window at an angle across the room--that and a bare stretch of floor.

The two men were not in the line of vision.
Burton's voice--it was unquestionably Burton speaking--came to Jimmie Dale now distinctly.
"No, I didn't! I tell you, I didn't! I--I hadn't the nerve." Jimmie Dale slipped his black silk mask over his face; and with extreme caution, on hands and knees, began to climb the stairs.
"So!" It was old Isaac now, in a half purr, half sneer.

"And I was so sure, my young friend, that you had.

I was so sure that you were not such a fool.

Yes; I could even have sworn that they were in your pocket now--what?
It is too bad--too bad! It is not a pleasant thing to think of, that little chair up the river in its horrible little room where--" "For God's sake, Isaac--not that! Do you hear--not that! My God, I didn't mean to--I didn't know what I was doing!" Jimmie Dale crept up another step, another, and another.