When a mile or more of this up-and-down travel had been traversed Fay halted and appeared to be at fault. The plateau was losing its rounded, smooth, wavy characteristics, and to the west grew bolder, more rugged, more cut up into low crags and buttes. After a long, sweeping glance Fay headed straight for this rougher country. Thereafter from time to time she repeated this action.

“Fay, how do you know you're going in the right direction?” asked Shefford, anxiously.

“I never forget any ground I've been over. I keep my eyes close ahead. All that seems strange to me is the wrong way. What I've seen, before must be the right way, because I saw it when they brought me from Surprise Valley.”

Shefford had to acknowledge that she was following an Indian's instinct for ground he had once covered.

Still Shefford began to worry, and finally dropped back to question Nas Ta Bega.

“Bi Nai, she has the eye of a Navajo,” replied the Indian. “Look! Iron-shod horses have passed here. See the marks in the stone?”

Shefford indeed made out faint cut tracks that would have escaped his own sight. They had been made long ago, but they were unmistakable.

“She's following the trail by memory—she must remember the stones, trees, sage, cactus,” said Shefford in surprise.

“Pictures in her mind,” replied the Indian.

Thereafter the farther she progressed the less at fault she appeared and the faster she traveled. She made several miles an hour, and about the middle of the afternoon entered upon the more broken region of the plateau. View became restricted. Low walls, and ruined cliffs of red rock with cedars at their base, and gullies growing into canyon and canyon opening into larger ones—these were passed and crossed and climbed and rimmed in travel that grew more difficult as the going became wilder. Then there was a steady ascent, up and up all the time, though not steep, until another level, green with cedar and pinon, was reached.