Reaching the upper story the detectives made a rush for the room La Croix had been occupying and found it empty.
"The birds have flown!" muttered Old King Brady in disgust.
"No wonder. We were caged up in the elevator so long they had ample time."
"They may have left some clew behind. Let us search the room."
This was done, and in the slop basin they found a letter torn up in small pieces.
Harry carefully gathered up the fragments and put them in his pocketbook.
"It's written in French," he commented, "but it may be of some use. I'll put the pieces together and we'll have it translated."
They failed to find anything else and went downstairs.
Returning to the clerk, they asked if La Croix had been seen.
"He did not come out this way," replied the man, shaking his head.