"You mean that it's hopeless to try? That the System is lost?" Roger Kay was appalled.
"I don't quite mean that," said North. "But what chance there is lies through this apparatus you're looking at now. Sit down; I'll explain while I work. You can help later, when I've explained the machine."
He began to tinker amidst the maze of wires.
"My discovery of trionite was purely accidental. It was empiric; not based on any theory. There were six or seven chemicals, and I recall the identity of only two of them. The others? Well, count the chemicals in the pharmacopoeia! The only way I could re-discover it would be by accident as I did before—and that would involve too many experiments and too much time. But the formula is buried somewhere in my subconscious mind. I might remember it."
Roger Kay eyed the box with some misgivings. "You mean this is—"
"The memory of everything we've ever done or seen is latent in our minds—in the molecular structure of the brain. Almost, I might say, in concentric layers. When the present crisis arose, I had been studying the human brain and the nature of thought and memory. Do you follow me?"
He looked up from his work and as Roger nodded, he saw how haggard and weary was the face of the elderly scientist.
"Consciousness is basically electrical in nature. The act of memory is the shift of that electrical impulse back to a buried stratum of the brain. But the shift is never complete; most of the consciousness stays in the present. We never remember anything perfectly."
"Then this machine is to—"
"To create a magnetic field of such a nature as to shift the consciousness as a whole. By shifting the magnetic field's intensity, I can move back the consciousness, or memory, to complete remembrance of any given moment of the past. In other words, under its influence, I hope to send back my memory to the moment when I jotted down the formula. Earlier or later won't do; I didn't memorize it at any time."