“That may be, but if so, we should be able to find the instrument with which the wrist was injured.  There would be marks of blood somewhere.”

“Exactly so!” said the Doctor, fixing his glasses as though preparing for an argument.  “But if it be that the patient has used some strange drug, it may be one that does not take effect at once.  As we are as yet ignorant of its potentialities—­if, indeed, the whole surmise is correct at all—­we must be prepared at all points.”

Here Miss Trelawny joined in the conversation: 

“That would be quite right, so far as the action of the drug was concerned; but according to the second part of your surmise the wound may have been self-inflicted, and this after the drug had taken effect.”

“True!” said the Detective and the Doctor simultaneously.  She went on: 

“As however, Doctor, your guess does not exhaust the possibilities, we must bear in mind that some other variant of the same root-idea may be correct.  I take it, therefore, that our first search, to be made on this assumption, must be for the weapon with which the injury was done to my Father’s wrist.”

“Perhaps he put the weapon in the safe before he became quite unconscious,” said I, giving voice foolishly to a half-formed thought.

“That could not be,” said the Doctor quickly.  “At least I think it could hardly be,” he added cautiously, with a brief bow to me.  “You see, the left hand is covered with blood; but there is no blood mark whatever on the safe.”

“Quite right!” I said, and there was a long pause.

The first to break the silence was the Doctor.

“We shall want a nurse here as soon as possible; and I know the very one to suit.  I shall go at once to get her if I can.  I must ask that till I return some of you will remain constantly with the patient.  It may be necessary to remove him to another room later on; but in the meantime he is best left here.  Miss Trelawny, may I take it that either you or Mrs. Grant will remain here—­not merely in the room, but close to the patient and watchful of him—­till I return?”

She bowed in reply, and took a seat beside the sofa.  The Doctor gave her some directions as to what she should do in case her father should become conscious before his return.

The next to move was Superintendent Dolan, who came close to Sergeant Daw as he said: 

“I had better return now to the station—­unless, of course, you should wish me to remain for a while.”

He answered, “Is Johnny Wright still in your division?”

“Yes!  Would you like him to be with you?” The other nodded reply.  “Then I will send him on to you as soon as can be arranged.  He shall then stay with you as long as you wish.  I will tell him that he is to take his instructions entirely from you.”

The Sergeant accompanied him to the door, saying as he went: