At the instant of their meeting he had stopped her and questioned her sharply.
That she was beyond all question insane was perfectly clear.
Her remarks were most incoherent, and yet they bore direct reference to the subject weighing most heavily upon the mind of Detective Hook: the robbery of the Webster Bank.
"He robbed the bank! He robbed the bank! I warned him, but he would not heed."
This was her sole answer to the questions the detective had pressed upon her, mingled with muttered words of thankfulness to the "bats in the wall."
Now nine men out of ten, under similar circumstances, would have arrested this woman at once.
Detective Hook was of a different sort.
Let him arrest this woman mad beyond a doubt—and, save for such vague information as could be drawn from her muttered ravings, her usefulness would at once be destroyed.
Follow her, and there was no telling where she might lead him—possibly to the abode of the bank-robbers themselves.
That she had seen those who blew open the vault, either enter or leave the bank, from her rambling words the detective became firmly convinced; so he let her go, and, dropping all else, followed her through the streets on that Sabbath morning. If nothing came of it he could at least arrest her whenever he pleased.