“That is not quite so common， is it？ Ah， me！ it’s a wicked world，and when a clever man turns his brains to crime it is the worst ofall. I think that I have seen enough now， Miss Stoner， and withyour permission we shall walk out upon the lawn.”
I had never seen my friend’s face so grim or his brow so darkas it was when we turned from the scene of this investigation.
We had walked several times up and down the lawn， neither MissStoner nor myself liking to break in upon his thoughts before heroused himself from his reverie.
“It is very essential， Miss Stoner，” said he， “that you shouldabsolutely follow my advice in every respect.”
“I shall most certainly do so.”
“The matter is too serious for any hesitation. Your life maydepend upon your compliance.”
“I assure you that I am in your hands.”
“In the first place， both my friend and I must spend the night inyour room.”
Both Miss Stoner and I gazed at him in astonishment.
“Yes， it must be so. Let me explain. I believe that that is thevillage inn over there？”
“Yes， that is the Crown.”
“Very good. Your windows would be visible from there？”
“Certainly.”
“You must confine yourself to your room， on pretence of aheadache， when your stepfather comes back. Then when youhear him retire for the night， you must open the shutters of yourwindow， undo the hasp， put your lamp there as a signal to us， andthen withdraw quietly with everything which you are likely towant into the room which you used to occupy. I have no doubtthat， in spite of the repairs， you could manage there for one night.”
“Oh， yes， easily.”
“The rest you will leave in our hands.”
“But what will you do？”
“We shall spend the night in your room， and we shall investigatethe cause of this noise which has disturbed you.”
“I believe， Mr. Holmes， that you have already made up yourmind，” said Miss Stoner， laying her hand upon my companion’ssleeve.
“Perhaps I have.”
“Then， for pity’s sake， tell me what was the cause of my sister’sdeath.”
“I should prefer to have clearer proofs before I speak.”
“You can at least tell me whether my own thought is correct，and if she died from some sudden fright.”
“No， I do not think so. I think that there was probably somemore tangible cause. And now， Miss Stoner， we must leave you forif Dr. Roylott returned and saw us our journey would be in vain.
Good-bye， and be brave， for if you will do what I have told you，you may rest assured that we shall soon drive away the dangersthat threaten you.”
Sherlock Holmes and I had no difficulty in engaging a bedroomand sitting-room at the Crown Inn. They were on the upper floor，and from our window we could command a view of the avenuegate， and of the inhabited wing of Stoke Moran Manor House.
At dusk we saw Dr. Grimesby Roylott drive past， his huge formlooming up beside the little figure of the lad who drove him. Theboy had some slight difficulty in undoing the heavy iron gates， andwe heard the hoarse roar of the doctor’s voice and saw the furywith which he shook his clinched fists at him. The trap drove on，and a few minutes later we saw a sudden light spring up among thetrees as the lamp was lit in one of the sitting-rooms.
“Do you know， Watson，” said Holmes as we sat together in thegathering darkness， “I have really some scruples as to taking youto-night. There is a distinct element of danger.”
“Can I be of assistance？”
“Your presence might be invaluable.”
“Then I shall certainly come.”
“It is very kind of you.”
“You speak of danger. You have evidently seen more in theserooms than was visible to me.”
“No， but I fancy that I may have deduced a little more. Iimagine that you saw all that I did.”
“I saw nothing remarkable save the bell-rope， and what purposethat could answer I confess is more than I can imagine.”
“You saw the ventilator， too？”
“Yes， but I do not think that it is such a very unusual thing tohave a small opening between two rooms. It was so small that a ratcould hardly pass through.”
“I knew that we should find a ventilator before ever we came toStoke Moran.”
“My dear Holmes！”
“Oh， yes， I did. You remember in her statement she said thather sister could smell Dr. Roylott’s cigar. Now， of course thatsuggested at once that there must be a communication betweenthe two rooms. It could only be a small one， or it would have beenremarked upon at the coroner’s inquiry. I deduced a ventilator.”
“But what harm can there be in that？”
“Well， there is at least a curious coincidence of dates. A ventilatoris made， a cord is hung， and a lady who sleeps in the bed dies. Doesnot that strike you？”
“I cannot as yet see any connection.”
“Did you observe anything very peculiar about that bed？”
“No.”
“It was clamped to the floor. Did you ever see a bed fastenedlike that before？”
“I cannot say that I have.”
“The lady could not move her bed. It must always be in thesame relative position to the ventilator and to the rope—or so wemay call it， since it was clearly never meant for a bell-pull.”
“Holmes，” I cried， “I seem to see dimly what you are hintingat. We are only just in time to prevent some subtle and horriblecrime.”
“Subtle enough and horrible enough. When a doctor doesgo wrong he is the first of criminals. He has nerve and he hasknowledge. Palmer and Pritchard were among the heads of theirprofession. This man strikes even deeper， but I think， Watson，that we shall be able to strike deeper still. But we shall havehorrors enough before the night is over； for goodness’ sake let ushave a quiet pipe and turn our minds for a few hours to somethingmore cheerful.”
About nine o’clock the light among the trees was extinguished，and all was dark in the direction of the Manor House. Two hourspassed slowly away， and then， suddenly， just at the stroke of eleven，a single bright light shone out right in front of us.
“That is our signal，” said Holmes， springing to his feet； “it comesfrom the middle window.”