“We could make gun powder if we could find a deposit of saltpeter. We already know where there’s a little sulphur. The guns would have to be converted to flintlocks, though, since we don’t have what we need for cartridge priming material. Worse, we’d have to use ceramic bullets. They would be inefficient⁠—too light, and destructive to the bores. But we would need powder for mining if we ever found any iron. And, if we can’t have metal bullets to shoot the Gerns, we can have bombs to blast them with.”

“Suppose,” Johnny Stevens said, “that we never do find the metals to make a ship. How will we ever leave Ragnarok if that happens?”

“There’s another way⁠—a possible way⁠—of leaving here without a ship of our own. If there are no metals we’ll have to try it.”

“Why wait?” Bob Craig demanded. “Why not try it now?”

“Because the odds would be about ten thousand to one in favor of the Gerns. But we’ll try it if everything else fails.”

George made, altered, and rejected four different types of crossbows before he perfected a reloading bow that met his critical approval. He brought it to where Humbolt stood outside the caves early one spring day when the grass was sending up the first green shoots on the southern hillsides and the long winter was finally dying.

“Here it is,” he said, handing Humbolt the bow. “Try it.”

He took it, noting the fine balance of it. Projecting down from the center of the bow, at right angles to it, was a stock shaped to fit the grip of the left hand. Under the crossbar was a sliding stock for the right hand, shaped like the butt of a pistol and fitted with a trigger. Mounted slightly above and to one side of the crossbar was a magazine containing ten short arrows.

The pistol grip was in position near the forestock. He pulled it back the length of the crossbar and it brought the string with it, stretching it taut. There was a click as the trigger mechanism locked the bowstring in place and at the same time a concealed spring arrangement shoved an arrow into place against the string.