“Would it be safe to venture into the place again in another guise?”

“They would know us.”

“Well,” said the old detective, with sudden inspiration, “I think I have a plan.”

“What is it?”

“Do you see the alley on this side of the building?”

“Yes.”

“Well, I think there is a small window on a level with the ground. It is directly over the table where those fellows sit.”

“Indeed!”

“It is true. I remember seeing it. Now, if we can only creep in there and either open the window or remove a pane of glass, we ought to hear every word.”

“Good! Let us try it.”