"It goes to the housekeeper's room."

"It looks newer than the other things?"

"Yes, it was only put there a couple of years ago."

"Your sister asked for it, I suppose?"

"No, I never heard of her using it. We used always to get what we wanted for ourselves."

"Indeed, it seemed unnecessary to put so nice a bell-pull there. You will excuse me for a few minutes while I satisfy myself as to this floor." He threw himself down upon his face with his lens in his hand and crawled swiftly backward and forward, examining minutely the cracks between the boards. Then he did the same with the wood-work with which the chamber was panelled. Finally he walked over to the bed and spent some time in staring at it and in running his eye up and down the wall. Finally he took the bell-rope in his hand and gave it a brisk tug.

"Why, it's a dummy," said he.

"Won't it ring?"

"No, it is not even attached to a wire. This is very interesting. You can see now that it is fastened to a hook just above where the little opening for the ventilator is."

"How very absurd! I never noticed that before."

"Very strange!" muttered Holmes, pulling at the rope. "There are one or two very singular points about this room. For example, what a fool a builder must be to open a ventilator into another room, when, with the same trouble, he might have communicated with the outside air!"

"That is also quite modern," said the lady.

"Done about the same time as the bell-rope?" remarked Holmes.

"Yes, there were several little changes carried out about that time."

"They seem to have been of a most interesting character–dummy bell-ropes, and ventilators which do not ventilate. With your permission, Miss Stoner, we shall now carry our researches into the inner apartment."

Dr. Grimesby Roylott's chamber was larger than that of his step-daughter, but was as plainly furnished. A camp-bed, a small wooden shelf full of books, mostly of a technical character, an armchair beside the bed, a plain wooden chair against the wall, a round table, and a large iron safe were the principal things which met the eye. Holmes walked slowly round and examined each and all of them with the keenest interest.