Then the sequoia towers became more scattered, as at the edge of a skyscraper district, until there were only a few left. And looking between the trunks of the last of the behemoths, Nirgal again hauled up short: on the other side of a narrow clearing, the canyon was blocked off by a wall of water. A sheer wall of water, filling the canyon right to the rim, hanging suspended over them in a smooth transparent mass.

Reservoir dam. Recently they had begun building them out of transparent sheets of diamond lattice, sunk in a concrete foundation; Nirgal could see this one running down both canyon walls and across the canyon floor, a thick white line.

The mass of water stood over them like the side of a great aquarium, turbid near the bottom, weeds floating in dark mud. Above them silver fish as big as the antelope flitted next to the clear wall, then receded into dark crystalline depths.

The three antelope pronged nervously back and forth before this barrier, the doe and fawn following the quick turns of the buck. As the hunters closed on them, the buck suddenly leaped away and crashed its head against the dam with a powerful thrust of its whole body— antlers like bone knives, thwack— Nirgal froze in fear, everyone froze at this violent gesture, so ferocious as to be human; but the buck bounced away, staggered. He turned and charged at them. Bola balls spun through the air and the line wrapped around his legs just above the hocks, and he crashed forward and down. Some of the hunters swarmed on him, others brought down doe and fawn in a hail of rocks and spears. A squeal cut off abruptly. Nirgal saw the doe’s throat cut with an obsidian-bladed dagger, the blood pouring onto the sand next to the foundation of the dam. The big fish flashed by overhead, looking down at them.

The woman with the green scarf was nowhere to be seen. Another hunter, a man wearing only necklaces, tilted his head back and howled, shattering the strange silence of the work; he danced in a circle, then ran at the clear wall of the dam and threw his spear straight at it. The spear bounced away. The exultant hunter ran up and slammed his fist against the clear hard membrane.

A woman hunter with blood on her hands turned her head to give the man a contemptuous look. “Quit fooling around,” she said.

The spear thrower laughed. “You don’t have to worry. These dams are a hundred times stronger than they need to be.”

The woman shook her head, disgusted. “It’s stupid to tempt fate.”

“It’s amazing what superstitions survive in fearful minds.”

“You’re a fool,” the woman said. “Luck is as real as anything else.”