“What is it, Petrie?” he said amazedly.  “Some kind of bird has been here, and recently.”  Inspector Weymouth in turn examined the marks.

“I never saw bird tracks like these, Mr. Smith,” he muttered.

Smith was tugging at the lobe of his ear.

“No,” he returned reflectively; “come to think of it, neither did I.”

He twisted around, looking at the man on the bed.

“Do you think it was all an illusion?” asked the detective.

“What about those marks on the window-sill?” jerked Smith.

He began restlessly pacing about the room, sometimes stopping before the locked safe and frequently glancing at Norris West.

Suddenly he walked out and briefly examined the other apartments, only to return again to the bedroom.

“Petrie,” he said, “we are losing valuable time. 
West must be aroused.”

Inspector Weymouth stared.

Smith turned to me impatiently.  The doctor summoned by the police had gone.  “Is there no means of arousing him, Petrie?” he said.

“Doubtless,” I replied, “he could be revived if one but knew what drug he had taken.”

My friend began his restless pacing again, and suddenly pounced upon a little phial of tabloids which had been hidden behind some books on a shelf near the bed.  He uttered a triumphant exclamation.

“See what we have here, Petrie!” he directed, handing the phial to me.  “It bears no label.”

I crushed one of the tabloids in my palm and applied my tongue to the powder.

“Some preparation of chloral hydrate,” I pronounced.

“A sleeping draught?” suggested Smith eagerly.

“We might try,” I said, and scribbled a formula upon a leaf of my notebook.  I asked Weymouth to send the man who accompanied him to call up the nearest chemist and procure the antidote.

During the man’s absence Smith stood contemplating the unconscious inventor, a peculiar expression upon his bronzed face.

“Andaman—­second,” he muttered.  “Shall we find the key to the riddle here, I wonder?”

Inspector Weymouth, who had concluded, I think, that the mysterious telephone call was due to mental aberration on the part of Norris West, was gnawing at his mustache impatiently when his assistant returned.  I administered the powerful restorative, and although, as later transpired, chloral was not responsible for West’s condition, the antidote operated successfully.

Norris West struggled into a sitting position, and looked about him with haggard eyes.

“The Chinamen!  The Chinamen!” he muttered.

He sprang to his feet, glaring wildly at Smith and me, reeled, and almost fell.

“It is all right,” I said, supporting him.  “I’m a doctor.  You have been unwell.”

“Have the police come?” he burst out.  “The safe—­try the safe!”

“It’s all right,” said Inspector Weymouth.  “The safe is locked—­ unless someone else knows the combination, there’s nothing to worry about.”