In the empty house they found that an entrance had been made into the adjoining warehouse, which had been used by a gang of thieves as a hiding-place for stolen goods.  In the little front shop these ingenious persons had fashioned an ingenious hiding-place by hollowing out a tunnel to the river.  Into this tunnel the water flowed at high tide; but when the tide was low an entrance could be effected from the river, by which the thieves could pass in and out, and in which they could safely deposit, in a chest in the slimy earth, property too valuable to be left above ground.

Carrie explained how Mrs. Higgs fraternized with the thieves, before she herself guessed who they were, and how she had got used to them before she learned their character, though not before she had grown suspicious about them.  How she had seen Dudley with Mrs. Higgs, without knowing who he was, and how she had set him down as a suspicious character from the furtive manner of his visits.  How she herself posted the two letters, the one to Edward Jacobs and the other to Dudley, which brought them to the place on the same day.  How she herself was sent out of the way on that occasion, and returned in time to witness, through the hole in the floor above, the stooping over the body by Dudley, and his drawing back covered with blood, which she took for the actual murder.  How Mrs. Higgs and Dudley had then left the house together, while she was too sick with fright to move.  How she had remained outside the house until she saw Max; and how, when he was gone, and Mrs. Higgs had come back, she found that the manner of the supposed old woman had changed toward her and grown unbearably cruel and harsh.  How she had been left for days and nights by herself, until she resolved to bear it no longer.  And how, when Mrs. Higgs had sent her to Dudley’s chambers with the message about Dick Barker, she had told her never to come back again.

Carrie added that she herself had always been treated with kindness, not only by the gang, of whom, indeed, they saw little, but by such of the men and boys on the barges which came to the wharf as knew her, and “winked” at her unauthorized tenancy of the deserted house.

In broad daylight, in the company of half a dozen policemen, Max and Dudley revisited the house together.  They found the holes in the wall through which “Mrs. Higgs” took stock of Max on the occasion of his first visit; they tested the ingenious device by means of which the middle boards in the front shop could be made to fall and deposit anything laid upon them in the tunnel beneath.  They found the hole in which Mrs. Higgs had stepped, and the pole which had been used to underpin the middle boards.  This hole extended under the floor of the kitchen, so that by creeping under the flooring from the one room to the other the pole could be withdrawn or replaced without the knowledge of a person in the front room.

This final discovery explained to Max the manner in which the body of Jacobs had been made to disappear while he himself was in the room with it.