He rolled him over on his back and began to chafe his hands. An officer in a naval uniform came through the door and with a swift glance around, bent over Dr. Bird. He raised one of the doctor's eyelids and peered closely at his eye and then sniffed at his breath.

"It's some anesthetic I don't know," he said. "I'll try a stimulant."

He reached in his pocket for a hypodermic, but Carnes interrupted him.

"Earlier in the evening Dr. Bird said they were using lethane," he said.

"Oh, that new gas the Chemical Warfare Service has discovered," said the surgeon. "In that case I guess it'll just have to wear off. I know of nothing that will neutralize it."

Without replying, Carnes began to feverishly search the pockets of the unconscious scientist. With an exclamation of triumph he drew out a bottle and uncorked it. A strong smell as of garlic penetrated the room and he held the opened bottle under Dr. Bird's nose. The doctor lay for a moment without movement, and then he coughed and sat up half strangled with tears running down his face.

"Take that confounded bottle away, Carnes!" he said. "Do you want to strangle me?"

He sat up and looked around.

"What happened?" he demanded. "Oh, yes, I remember now. That brute was about to operate on me. How did you get here?"

"Never mind that, Doctor. Are you all right?"

"Right as a trivet, old dear. How did you get here so opportunely?"

"I was a little slow in locating Lieutenant Maynard and the marines.

When we got here I was afraid that we couldn't find the door, so I took Maynard and a detail around to the back and I went up to the top and slid down our cord and looked in the window. You were unconscious and Slavatsky was bending over you with a needle in his hand. I was about to try a shot at him when something called their attention to the men in front and I squeezed through the window and dropped in on them. They didn't seem any too glad to see me, but I overlooked that and insisted on inviting the rest of my friends in to share in the party. That's all."

"Carnes," said the Doctor, "you're probably lying like a trooper when you make out that you did nothing, but I'll pry the truth out of you sooner or later. Now I've got to get to work. Send for Lieutenant Maynard."

One of the marines went out to get the flyer, and Dr. Bird stepped to the cabinet from which Slavatsky had taken his record book earlier in the evening and took out the leather-bound volume. He opened it and had started to read when Lieutenant Maynard entered the cave.

"h.e.l.lo, Maynard," said the Doctor, looking up. "Are the rest of the party on their way?"

"They will be here in less than two hours, Doctor."

"Good enough! Have some one sent to guide them here. In the meanwhile, I'm going to study these records. Keep the prisoners quiet. If they make a noise, gag them. I want to concentrate."

For an hour and a half silence reigned in the cave. A stir was heard outside and Admiral Clay, the President's personal physician, entered leading a stout gray-haired man. Dr. Bird whistled when he saw them and leaped to his feet as another figure followed the admiral.

"The President!" gasped Carnes as the officers came to a salute and the marines presented arms.

The President nodded to his ex-guard, acknowledged the salute of the rest and turned to Dr. Bird.

"Have you met with success, Doctor?" he asked.

"I have, Mr. President; or, rather, I hope that I have. At the same time, I would rather experiment on some other victim of their deviltry than the one you have brought me."

"My decision that the one I have brought shall be the first to be experimented on, as you term it, is unalterable."

Dr. Bird bowed and turned to the dwarf who had been a sullen witness of what had gone on.

"Slavatsky," he said slowly, "your game is up. I have witnessed one of your brain transfusions and I know the method. I gather from your notes that the menthium you have hidden in that cabinet is still as potent as when it was first extracted from a living brain, but in this case I am going to draw it fresh from one of your gang. Some of the details of the operation are a little hazy to me, but those you will teach me. I am going to restore this man to the condition he was in before you did your devil's work on him and you will direct my movements. Just what is the first step in removing the menthium from a brain?"

The dwarf maintained a stubborn silence.

"You refuse to answer?" asked the Doctor in feigned surprise. "I thought that you would rather instruct me and have me try the operation first on other men. Since you prefer that I operate on you first, I will be glad to do so."

He stepped to the opposite wall and in a few moments had opened the dwarf's hiding place and taken out the flask of menthium.

"Carson," he said, "after you had watched Slavatsky inject menthium into Willis, you took lethane and expected him to inject menthium into your brain. Instead of doing so he withdrew a portion from your brain and put it in this flask. I have reason to believe from his secret records which I found in the cabinet with this flask that he has done so regularly. Are you willing to instruct me while I remove the menthium from him?"

"The dirty swine!" shouted Carson. "I'll do anything to get even with him, but I have never performed the operation. Only Slavatsky and Willis have operated."

"Will you help me, Willis? asked Dr. Bird.

"I'll be glad to, Doctor. I am sick of this business anyway. At first, Slavatsky just planned to give us abnormally keen brains, but lately he has been talking of setting himself up as Emperor of the World, and I am sick of it. I think I would have broken with him and told all I know, soon, anyway."

"Throw him in that chair," said Dr. Bird.

Despite the howlings and strugglings of the dwarf, three of the marines strapped him in the chair beneath the tube. The dwarf howled and frothed at the mouth and directed a final appeal for mercy to the President.

"Spare me, Your Excellency," he howled. "I will put my brains at your service and make you the greatest mentality of all time. Together we can conquer and rule the world. I will show you how to build hundreds of ships like mine--"

The President turned his back on the dwarf and spoke curtly.

"Proceed with your experiments, Dr. Bird," he said.

Slavatsky directed his appeals to the doctor, who peremptorily silenced him.

"I told you a few hours ago, Slavatsky, that the time might come when I would remember your threats against me. I will show you the same mercy now as you promised me then. Carnes, put a cone over his face."

Despite the howls of the dwarf, the operative forced an anesthesia cone over his face and Dr. Bird turned to the valve of the lethane cylinder. With Willis directing his movements, he turned on the ray for three minutes and removed the unconscious dwarf to the operating table. He took the long-needled syringe from a case and sterilized it and then turned to the President.

"I am about to operate," he said, "but before I do so, I wish to explain to all just what I have learned and what I am about to do.

With that data, the decision of whether I shall proceed will rest with you and Admiral Clay. Have I your permission to do so?"

The President nodded.

"When I first read of these amnesia cases, I took them for coincidences--until you consulted me and gave me an opportunity to examine one of the victims. I found a small puncture at the base of the brain which I could not explain, and I began to dig into old records. I knew, of course, of Sweigert of Vienna, and the extravagant claims he had put forward in 1911. He was far ahead of his time, but he mixed up some profound scientific discoveries with mysticism and occultism until he was discredited. Nevertheless, he continued his experiments with the aid of his princ.i.p.al a.s.sistant, a man named Slavatsky.

"Sweigert's theory was that intellectuality, brain power, intelligence, call it what you will, was the result of the presence of a fluid which he called 'menthium' in the brain. He thought that it could be transferred from one person to another, and with the aid of Slavatsky, he experimented on himself. He removed the menthium from an unfortunate victim, who was reduced to a state of imbecility, and Slavatsky injected the substance into Sweigert's brain. The experiment resulted fatally and Slavatsky was tried for murder. He was acquitted of intentional murder but was imprisoned for a time for manslaughter.

He was released when the Austro-Hungarian Empire was broken up, and for a time I lost track of him.