From the nature of the case it seemed clear that the entrance to the cellar, if one existed, would be hidden. It was therefore for secret doors or moving panels that he must look.
He began by ascertaining the thickness of all the walls, noting the size of the rooms so as to calculate those he could not measure directly. He soon found that no wall was more than six inches thick, and none could therefore contain a concealed opening.
This narrowed his search. The exit from the building could only be through a trap-door in the floor.
Accordingly he set to work in the office, crawling torch in hand along the boards, scrutinizing the joints between them for any that were not closed with dust, feeling for any that might be loose. But all to no purpose. The boards ran in one length across the floor and were obviously firmly nailed down on fixed joists.
He went to the bedroom, rolling aside the mats which covered the floor and moving the furniture back and forwards. But here he had no better result.
The remainder of the shed was floored with concrete, and a less meticulous examination was sufficient to show that the surface was unbroken. Nor was there anything either on the wharf itself or in the enclosure behind the shed which could form a cover to a flight of steps.
Sorely disappointed, Willis returned once more to the office, and sitting down, went over once again in his mind what he had done, trying to think if there was a point on the whole area of the depot which he had overlooked. He could recall none except the space beneath a large wardrobe in the next room which, owing to its obvious weight, he had not moved.
“I suppose I had better make sure,” he said to himself, though he did not believe so massive a piece of furniture could have been pulled backwards and forwards without leaving scratches on the floor.
He returned to the bedroom. The wardrobe was divided into two portions, a single deep drawer along the bottom, and above it a kind of large cupboard with a central door. He seized its end. It was certainly very heavy; in fact, he found himself unable to move it.
He picked up his torch and examined the wooden base. And then his interest grew, for he found it was strongly stitch-nailed to the floor.