However, Andy determined that, come what might, he would defend his trust, "or perish in the attempt." But, while he was coming to this determination, he heard the door of the adjoining chamber open softly, and then he could hear steps along the corridor.

Evidently, the thief had not found out the actual character of his booty, but was going off under the impression that it was valuable.
"Maybe he'll come back," thought Andy.

"I guess I'd better go down and give notice at the desk.

Then, if he comes back, he'll get into hot water." He hastily dressed himself, and, locking his door, went downstairs.
First, however, he removed the money from under his pillow, and put it into his pocket.

He found the clerk at the desk.
"Has the man that came in with me gone out ?" asked Andy.
"Mr.Marvin ?" "Yes." "He went out about five minutes ago." "Did he say anything about coming back ?" "He said it would be late when he returned.