“That’s the bit I’m having trouble with,” Murphy confessed, shaking his head.
“Well, you’ve seen it for yourself. We’re standing on the surface of a rotating sphere, the Earth. Just below us is another and slightly smaller rotating sphere which has moved off centre until the surfaces are touching at one side. As the spheres turn, corresponding points will move closer together until they meet at the contact zone, but as the rotation continues they have to move apart again. Twelve hours later, half a day, they’ll be at maximum separation, with the inner point far beneath the outer point.
“That’s why the Avernians rise up through the floor and sink back down again. The best time to try making contact is when they’re at the top of the curve and the downward motion hasn’t yet begun. What do you call it when a piston reaches the top of its stroke?”
“Top dead centre,” Snook supplied.
“That’s when we’ve got to try to make the first contact with the Avernians—when they’re at top dead centre—and that’s why there’s no time to waste. Tomorrow morning, and for three mornings after that, top dead centre will occur at fairly convenient positions for us—after that it will take place in the air, higher and higher above the mine.”
“Four chances,” Quig said. “Being strictly realistic about it, Boyce, what can you hope to achieve even if you strike lucky the very first time? Four brief meetings would hardly give the Avernians time to react.”
“Oh, we wouldn’t be limited to four meetings,” Ambrose said airily.
“But you just said…”
“I said I was hoping for first contact while top dead centre is in a convenient location, that is, either below ground or on it. After that, when top dead centre is in the air above the mine, we would be able to have quite long meetings.”
“For God’s sake, how?”
“Think it out for yourself, Des. If you wanted to rise slowly into the air, hover for a while and sink vertically downwards again—what sort of machine would you use?”
Quig’s eyes widened. “A helicopter.”
“Exactly! I provisionally chartered one today.” Ambrose beamed at his audience, like a fond parent surprising his children with an extravagant gift. “Now that we’ve got that out of the way, let’s discuss the immediate problems for a while.”
Listening to the conversation, Snook once again began to revise his opinions of Boyce Ambrose. The category he had invented for him, playboy scientist, still seemed appropriate -but Ambrose was playing in earnest, like a man who had a definite goal in mind and was determined that nothing would prevent him from reaching it.
Although all work had stopped at the mine, the perimeter fence was still floodlit and the security patrols were in operation. Snook felt vulnerable and selfconscious as he approached the gate, accompanied by George Murphy and the other four members of the group, under the interested stares of the mine guards. He was carrying six squares of heavy cardboard, placards which Ambrose had insisted on making, and they were proving strangely difficult to handle. The night breezes were slight, but even the gentlest puff of air was enough to make the smooth cards twist and slither in his grasp. He began to swear over Cartier’s ruling that they could not bring a vehicle into the enclosure. .
Murphy, who was well known to the guards, was nevertheless stopped by them and had to produce a letter signed by Cartier before the group were admitted. They straggled through the gate with the various boxes of equipment Ambrose had produced. Prudence remained close to Ambrose, talking quietly to him all the while. This fact produced a fretful resentment in Snook. He explained it to himself by reasoning that she was, if not actually a hindrance, certainly the least useful member of the group and it was therefore inordinate for her to occupy so much of the leader’s time. Another level of his mind, one which was immune to deception, regarded this explanation with contempt.
“I see they’ve taken your advice—too late.” Murphy nudged Snook and pointed at new notices, in red lettering, which stated that all below-ground workers were required to hand in their Amplite glasses pending the installation of improved lighting systems in the mine.
“It helps cover up for the closure,” Snook said, his attention elsewhere. He had just noticed that two army jeeps were parked in the darkness beyond the gatehouse, each of them containing four men of the Leopard Regiment. As soon as the soldiers saw Prudence they began whooping and jeering. The two drivers switched on spotlights and directed them at Prudence’s legs, and one soldier—to the cheers of his comrades—left his vehicle and ran up to her for a close inspection. She walked on calmly, looking straight ahead, holding on to Ambrose’s arm. Ambrose, too, ignored the soldier.
Snook took his Amplites from his breast pocket, put them on and looked towards the jeeps. In the blue pseudo-radiance he saw that a lieutenant, the same one who had been at his house in the morning, was sitting in one of the vehicles with his arms folded, unperturbed by the behaviour of his men.
“What do these bastards think they’re doing?” Murphy whispered fiercely, starting towards the nearby soldier.
Snook restrained him. “It isn’t our problem, George.”
“But that ape needs a kick where it’ll do him the most damage.”
“Boyce brought her here,” Snook said stolidly. “Boyce will have to look after her.”
“What’s the matter with you, Gil?” Murphy stared at Snook, then gave a low chuckle. “I get it. I thought I saw you doing a bit of quiet mooning in that direction, but I wasn’t sure.”
“You saw nothing.”
Murphy remained quiet for a moment as the soldier grew tired of the game and rejoined his comrades. “Was there nothing doing, Gil? Sometimes those aristocratic types go for a bit of rough—just for a change, you know.”
Snook kept his voice steady. “What’s discipline like in the Leopard Regiment? I thought they were kept on a pretty tight rein.”
“They are.” Murphy became thoughtful. “Was there an officer watching the show?”
“Yes.”
“That doesn’t have to mean anything.”
“I know what it doesn’t have to mean.”
They reached the mine head and Snook felt his concern about the behaviour of the soldiers abruptly vanish as it came to him that, in all probability, he was due for another encounter with the silent, translucent beings who walked in the depths of the mine. It was all right for Ambrose, who had never seen the apparitions, to talk knowledgeably about geometries and planetary movements—facing the reality of the blue ghosts was another matter entirely. Snook discovered in himself an intense reluctance to go underground, but he concealed it as the group assembled at the continuous hoist and Murphy set the machinery going. The Avernians’ mouths were what he dreaded seeing most, the inhumanly wide, inhumanly mobile slits which at times seemed to express a sadness beyond his comprehension. It occurred to Snook that Avernus might be an unhappy world, well named after a mythological hell.
“I’ll go down first because I know the level we want,” Murphy announced. “The hoist moves continuously so you’ll have to step off smartly when you see me, but don’t worry -it’s as easy as using an escalator. If you don’t get out in time, stay on until you reach the gallery below, get off there, walk round to the ascending side and come up again. We haven’t lost a visitor yet.”
The others laughed appreciatively, their spirits recovering from the uneasiness which had been inspired by the near-incident at the gate. They stepped into descending cages two by two. Snook going last with his awkward bundle of cards. His ears popped during the patient, rumbling descent. When he reached the circular landing at Level Three he found Ambrose already holding court, assigning people to the various radial tunnels. The radiation generator, which was the size of a small suitcase, was to be left at the hoist and carried to anyone who shouted that he had found an Avernian building.