He dangled it on its cable inside the flak tear, pulled the goggles over his eyes, and flicked the switch with his thumb.
The Walter goggles made the world inside the tunnel no darker than it actually was, but knowing that he would now be unable to see any gleam of light in the tunnel, should one appear from somewheresay, in the ultimate glare of hydrogen fusionincreased the pressure of blackness on his brain. Back on the truck the frequency-analyzer began its regular, meaningless peeping, scanning the possible cortical output bands in order of likelihood: First the 0.5 to 3.5
cycles/second band, the delta wave, the last activity of the brain detectable before death; then the four to seven c.p.s.
theta channel, the pleasure-scanning waves which went on even during sleep; the alpha rhythm, the visual scanner, at eight to thirteen c.p.s.; the beta rhythms at fourteen to thirty c.p.s. which mirror the tensions of conscious computation, not far below the level of real thought; the gamma band, where
The goggles lit.
… And still the dazzling sky-blue sheep are grazing in the red field under the rainbow-billed and pea-green birds… .
McDonough snatched the goggles up with a gasp, and stared frantically into the blackness, now swimming with resi-dual images in contrasting colors, melting gradually as the rods and cones in his retina gave up the energy they had ab-sorbed from the scene in the goggles. Curiously, he knew at once where the voice had come from: it had been his mo-ther’s reading to him, on Christmas Eve, a story called “A Child’s Christmas in Wales.” He had not thought of it in well over two decades, but the scene in the toposcope goggles had called it forth irresistibly.