is not described in great detail, but it is mentioned that the recording is used to create a duplicate or "dupe" which is stored in the "restoration bank", and at one point a lecturer says that "The experience of the years, the neurograms, simple memory circuits—neurons, if you wish—stored among these nerve cells, are transferred to the dupe, a group of more than ten billion molecules in colloidal suspension. They are charged much as you would charge the plates of a battery, the small neuroelectrical impulses emanating from your brain during the recording session being duplicated on the molecular structure in the solution." During restoration, they take the dupe and "infuse it into an empty brain", and the plot turns on the fact that it is possible to install one person's dupe in the body of a completely different person. An early example featuring uploaded minds in robotic bodies can be found in Frederik Pohl's story "The Tunnel Under the World" from 1955. In this story, the protagonist Guy Burckhardt continually wakes up on the same date from a dream of dying in an explosion. Burckhardt is already familiar with the idea of putting human minds in robotic bodies, since this is what is done with the robot workers at the nearby Contro Chemical factory. As someone has once explained it to him, "each machine was controlled by a sort of computer which reproduced, in its electronic snarl, the actual memory and mind of a human being ... It was only a matter, he said, of transferring a man's habit patterns from brain cells to vacuum-tube cells." Later in the story, Pohl gives some additional description of the procedure: "Take a master petroleum chemist, infinitely skilled in the separation of crude oil into its fractions. Strap him down, probe into his brain with searching electronic needles. The machine scans the patterns of the mind, translates what it sees into charts and sine waves. Impress these same waves on a robot computer and you have your chemist. Or a thousand copies of your chemist, if you wish, with all of his knowledge and skill, and no human limitations at all." After some investigation, Burckhardt learns that his entire town had been killed in a chemical explosion, and the brains of the dead townspeople had been scanned and placed into miniature robotic bodies in a miniature replica of the town (as a