THE ANCIENT PEOPLE
Biltmer's gun-room. As they crossed the pasture land the clumsy slicker kept catching in the lacings of his leggings.
"Why don 't you drop that thing?" Thea asked. "I won't mind a shower. I 've been wet before."
"No use taking chances."
From the canyon they were unable to watch the sky, since only a strip of the zenith was visible. The flat ledge about the watch-tower was the only level spot large enough for single-stick exercise, and they were still practicing there when, at about four o'clock, a tremendous roll of thunder echoed between the cliffs and the atmosphere suddenly became thick.
Fred thrust the sticks in a cleft in the rock. "We 're in for it, Thea. Better make for your cave where there are blankets." He caught her elbow and hurried her along the path before the cliff-houses. They made the half-mile at a quick trot, and as they ran the rocks and the sky and the air between the cliffs turned a turbid green, like the color in a moss agate. When they reached the blanketed rock room, they looked at each other and laughed. Their faces had taken on a greenish pallor. Thea's hair, even, was green.
"Dark as pitch in here," Fred exclaimed as they hurried over the old rock doorstep. "But it 's warm. The rocks hold the heat. It 's going to be terribly cold outside, all right." He was interrupted by a deafening peal of thunder. "Lord, what an echo! Lucky you don't mind. It 's worth watching out there. We need n't come in yet."
The green light grew murkier and murkier. The smaller vegetation was blotted out. The yuccas, the cedars, and piñons stood dark and rigid, like bronze. The swallows flew up with sharp, terrified twitterings. Even the quaking asps were still. While Fred and Thea watched from the doorway, the light changed to purple. Clouds of dark vapor, like chlorine gas, began to float down from the head of the canyon and hung between them and the cliff-houses
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