There upon the gleaming black ladroxite bench-top was a thing of silvery beauty, of exquisitely delicate workmanship, and of utterly strange character!

Its central portion was a silver metal disc, about five inches across and half an inch thick. From its outer rim a number of tapering tentacular appendages snaked out for lengths varying from a few inches to over a foot.

The disc itself was a hollow case, with its surface curved as though to fit just inside the top of a human skull. Ramsey had cut away the top of the case, revealing an interior filled with a maze of tiny coils and other mechanism of almost microscopic fineness. In the center of the coils was a little blue globe the size of a small marble...

“There,” he said, “is a sending and receiving set that is the most marvelously conceived piece of apparatus I have ever seen!”
“You got all of that out of that bird’s skull!” Barnes exclaimed.
Ramsey nodded. “That cadaver was nothing but a robot.”
“You mean he was a mechanical figure?” Amber asked incredulously.
“No, no!” Ramsey growled impatiently. “He was living flesh and blood. Before that apparatus was inserted in his skull he was probably as normal as anyone. But when once the mechanism was set into his brain he had no more power of volitional movement than a robot plane. He was, to all intents and purposes, merely an ‘extension’ of the person on the other end of the receiving and transmitting apparatus.”
Ramsey pointed to the tentacle-like extensions from the central disc. They were as thick as a man’s finger where they left the disc, then tapered and branched into filaments of hairlike fineness.

('the most marvelously conceived piece of apparatus I have ever seen')

THOSE wires,” Ramsey said, “were connected with every vital part of the carrier’s brain. Some of them ran to the optic and auditory nerves, picking up sight and sound which the mechanism in the disc transmitted to the distant operator. Others were connected with the areas of voluntary muscular movement. They received impulses from the operator and moved corresponding parts of the carrier’s body in response.”
“But what happened to the higher centers of the carrier’s mind?” Barnes asked. “Did he have any consciousness of his own left, to realize what was being done to him?”
Ramsey spread his hands in an eloquent gesture.
“Who knows? If he did have any consciousness it must have been a terrible thing, to be helplessly walled up a prisoner in his own brain, completely powerless even to move a finger of his own volition!”
“What was used to make contact between the carrier and the operator?” Amber asked. “Some new and improved form of radio, I suppose.”
“My dear girl,” Ramsey said grufily, “whatever the method was that was used, it was as far superior to radio as radio itself is to the rock-thumping code messages of a Venusian swamp savage. I haven’t the faintest idea what the source of power Was. Even the basic principles of that unbelievably compact little piece of machinery are different from anything previously known to Science. I can make a reasonably accurate guess as to the general nature of the apparatus, but I haven’t the slightest conception of how it works.”