A host of images fought for possession of his tired mind, as he plunged through thin streamers of paling cloud. Green dots on the World Map. The greens and blues of the Yggdrasil--and in what nightmare worlds had Hoderson found his inspiration? The blue-tinted sketches one of Thorn's dreamers had made of the world of his nightmares. A sallow image of Thorn's face altered and drawn by pain, such an image as might float into the mind of one who watches too long by a sickbed. The looks on the faces of Conjerly and Tempelmar--that fleeting impression of a hostile strangeness. The hint of a dark alien presence in the depths of his own mind. The Blue Lorraine grew gigantic, loomed as a vast, shadow-girt cliff, its topmost pinnacles white with frost although the night below had been summery. There were already signs of a new day beginning. Here and there freighters clung like beetles to the wall, discharging or receiving cargo through unseen ports. Some distance below a stream of foodstuffs for the great dining halls, partly packaged, partly not, was coming in on a subtronic current. Off to one side an attendant shepherded a small swarm of arriving schoolchildren, although it was too early yet for the big crowds. Clawly swooped to a landing stage, hovered for a moment like a bird, then dropped. In the ante-room he and another early arriver helped each other remove and check their flying togs. He was breathing hard, there was a deafness and a ringing in his ears, he rubbed his chilled fingers. He should not have made such a steep and swift ascent. It would have been easier to land at a lower stage and come up by levitator. But this way was more satisfying to his impatience. And there was less chance of someone following him unseen. A levitating current wafted him down a quarter mile of mainstem corridor to the district of the psychologists. From there he walked. He looked around uneasily. Only now did real doubt hit him. What if Conjerly were right? What if he were merely dragging up ancient superstitions, foisting them on a group of overspecialized experts, Thorn included? What if the world-threat he had tried to sell to the World Executive Committee were just so much morbid nonsense, elaborately bastioned by a vast array of misinterpreted evidence? What if the darker, crueler, deviltry-loving side of his mind were more in control than he realized? He felt uncomfortably like a charlatan, a mountebank trying to pipe the whole world down a sinister side street, a chaos-loving jester seeking to perpetrate a vast and unpleasant hoax. It was all such a crazy business, with origins far more dubious than he had dared reveal even to Thorn, from whom he had no other secrets. Best back down now, at least quit stirring up any more dark currents. But the other urge was irresistible. There were things he had to know, no matter the way of knowing.