"Goodness," exclaimed Mrs. Bagley, "all I want is a brief idea. I wouldn't understand the principles at all."
"Well, then, my mother, as a cerebral surgeon, knew the anatomy of the human brain. My father, as an instrument-maker, designed and built encephalographs. Together, they discovered that if the great waves of the brain were filtered down and the extremely minute waves that ride on top of them were amplified, the pattern of these superfine waves went through convolutions peculiar to certain thoughts. Continued research refined their discovery.
"Now, the general theory is that the cells of the brain act sort of like a binary digital computer, with certain banks of cells operating to store sufficient bits of information to furnish a complete memory. In the process of memorization, individual cells become activated and linked by the constant repetition.
"Second, the brain within the skull is a prisoner, connected to the 'outside' by the five standard sensory channels of sight, sound, touch, taste, and smell. Stimulate a channel, and the result is a certain wave-shape of electrical impulse that enters the brain and—sort of like the key to a Yale lock—fits only one combination of cells. Or if no previous memory is there, it starts its own new collection of cells to linking and combining. When we repeat and repeat, we are deepening the groove, so to speak.
"Finally comes the Holden Machine. The helmet makes contact with the skull in those spots where the probes of the encephalograph are placed. When the brain is stimulated into thought, the brain waves are monitored and recorded, amplified, and then fed back to the same brain-spots. Not once, but multifold, like the vibration of a reed or violin string. The circuit that accepts signals, amplifies them, returns them to the same set of terminals, and causes them to be repeated several hundred times per millisecond without actually ringing or oscillating is the real research secret of the machine. My father's secret and now mine."
"And how do we use it?"
"You want to memorize a list of ingredients," said James. "So you will put this helmet on your head with the cookbook in your hands. You will turn on the machine when you have read the part you want to memorize just to be sure of your material. Then, with the machine running, you carefully read aloud the passage from your book. The vibrating amplifier in the machine monitors and records each electrical impulse, then furnishes it back to your brain as a successive series of repetitious vibrations, each identical in shape and magnitude, just as if you had actually read and re-read that list of stuff time and again."
"And then I'll know it cold?"
James shook his head. "Then you'll be about as confused as you've ever been. For several hours, none of it will make sense. You'll be thinking things like a 'cup of salt and a pinch of water,' or maybe, 'sugar three of mustard and two spoonthree teas.' And then in a few hours all of this mish-mash will settle itself down into the proper serial arrangement; it will fit the rest of your brain-memory-pattern comfortably."
"Why?"