"Show me where that goes," said Thorinn, pointing.
In the crystal, the box-shape dwindled, receding, while more of the tunnel appeared. Presently the tunnel crossed a shaft as big as itself.
"And that? Where does it go?"
The picture shrank again; now he could see that the shaft met another tunnel, and above that the dark background ended.
"Is that the Midworld?"
"What is the Midworld?"
"The top of the earth, where there are no more caves."
"That is the Midworld."
Thorinn pointed again. "How far is it from here to the top?"
"What is how far?"
"How far," Thorinn said, waving his arms by way of explanation. "How many ells?"
"What are ells?"
Thorinn sat down on the floor and stared at the box in exasperation. "Ells are—well, anybody knows that. Ells are how long something is." He spread his hands apart. "This is an ell." The box said, "How long are you?"
"You mean how tall. Two ells. I'm two ells tall."
In the crystal, two yellow marks appeared. "How many?"
"Two."
One of the marks vanished. "How many?"
"One."
Two more appeared. "How many?"
"Three."
Another mark. "How many?"
"Four."
The box, Thorinn realized, did not even know how to count.
So they went on until they got to twenty-one, and then the box said, "Two tens are twenty?"
"Yes, that's right, and three tens are thirty."
"And four tens?"
"Four tens are forty. Five tens are fifty, six tens are sixty." At a hundred and ten, the box stopped him again.
"Twenty tens are two hundred?"
"Yes."
"It is three hundred and thirty-two ells from here to the top." Thorinn sat awhile with his chin on his fist. The geas had never prevented him from going up when there was no other way to go; therefore he could surely get into the tunnel. Then, if he could but gain the Midworld, though the geas would be on him still, he need only keep away from pits and chasms, for no magic could make a man go down through the solid earth. But he could never climb that shaft against the geas; and the geas could be removed only by its maker, or by a greater magician. Struck by a thought, he said, "Box, can you do magic?"
"What is magic?"
"Magic is—well, for instance, a spell that makes something happen."
"What is a spell?"
"Well, suppose you want to find something." Thorinn picked up two jewels from the heap, a red one and a green; he tossed the red one over his shoulder, hearing it click and roll down the aisle. Then he picked up the green one and chanted three times, "Brother, find your brother." He threw the green jewel, marking where it went. When he found it, it lay beside the red one.
"You see, that was a spell—I found the red one by making the green one go to the same place."
"Not the spell. You found the red one."
Incredulous, Thorinn tried to explain again, but the box insisted that it knew nothing of spells, and he gave up. Perhaps the magician who had made the box had taken care to teach it no magic, for fear it would become greater than himself.
At any rate, why should he not attempt some magic of his own? Many times he had watched Goryat casting spells to keep wolves away, or to make sure the mares would come fresh in the spring and the foals be born alive. Supposing his spell worked but poorly, or that it lasted only a short time, still it might be enough for his purpose. He brooded over this awhile, then set aside certain articles from the heap—a tiny figurine of an old bearded man, who reminded him somewhat of Goryat; slender bits of wood painted with designs in red; a box full of a fine gray powder. These he wrapped carefully and put away in his wallet. Then he began to consider what else he could take and what he must leave behind.
The magic jug was a problem. He thought of hanging it from his belt, but that would be awkward, and unless he could contrive some sort of cover for it, the jug would be spilling water down his leg; whereas if he put it in his wallet, it would take up too much room. He could fill the jug with jewels, but then would the water run over?
He remembered that when he had first taken the jug from its wrapping, there had been no water in it, or at any rate only a drop. Was it being wrapped up that made the difference? He cut a piece of the transparent stuff, wrapped it around the jug after pouring the water out, and tied it tightly with strips of the same material. Later, when he came back from a trip to gather food, he opened it and it was still dry. He filled it to the brim with jewels, wrapped it again and put it in his wallet. The next thing was to be sure he knew how to find the exit from the cavern.
"Box, show me this cave again."
The crystal lighted; the same bright hollow shape appeared.
"How far is it from here to the hole in the roof?"
A short yellow line appeared across the width of the cavern. "It is two hundred and ninety-one ells—" A longer line, lengthwise, almost to the end. "—and eight hundred and thirty-eight ells."
"Eight hundred ells? How big is this cave?"
"It is eight hundred and fifty ells long, and fifteen ells tall, and three hundred and nineteen ells—"
"Three hundred and nineteen ells wide?"
"Yes, three hundred and nineteen ells wide."
Thorinn was silent in amazement. "Is it all like this—all full of things?"
"It is all full of things."
Thorinn tried to imagine that, and could not. "Box, who made this cave?"
"What is made?"
Thorinn tried to explain, and grew hot-faced with exasperation. "Well, look here," he said finally, and picked up his light-box. "I made this box. I cut these pieces of wood and glued them together, and I fitted the pieces of mica in here at the ends—well, one of them is gone now, I lost it in the river. Then I made the lid and put it on here, and then the box was made, you see. I made it." In the crystal, an image of Thorinn appeared, fitting little pieces of wood together. It was over in a moment, and the figure held a light-box in its hand.
"You made this box?"
"That's right. Now who made all this? Who made you?"
"A box made me."
"You mean you made yourself?"
"I mean I made me?"
"Well, did you?"
"A box made this box." In the crystal appeared a huge black engine, out of the end of which, one after another, were dropping little black boxes, each with a glint of crystal inside it. They floated away out of sight; it made Thorinn dizzy to watch them.
"You mean an engine. An engine made you—and all these other things?"
"Engines made me and all these other things."
"Well, but who made the engines?"
"Engines made the engines."
Thorinn gave it up. He made the box show him the picture of the cave again, then what was around it. In the new picture, the cave was a tiny bright shape at the top, while all around it other transparent passages ran off in every direction, some twisting, some straight, leading to other caverns. His idea had been to make sure there was no better way up to the Midworld than the one the box had showed him before, but as he asked the box to show him more and still more, he grew fascinated by the maze of passages, caverns, and shafts crisscrossing each other; there seemed to be no end to it. New lines kept floating into the picture while the old ones grew smaller and closer together. "How did it ever come to be like that?" he asked. "The whole Underworld?"
In the crystal, the network of lines vanished and a man's face appeared, brown and smiling; at least Thorinn supposed he was a man, though he was beardless. His black hair was cut short and combed back, exposing his ears and forehead. His lips moved. After a moment the box said, "This is the world." Behind the brown-faced man a big green and blue mottled ball was floating against a background of darkness. The man's lips went on moving, but no sound came. The ball receded, grew very small.