Ladd pursued a zigzag course southward across the desert, trotting down the aisles, cantering in wide, bare patches, walking through the clumps of cacti.  The desert seemed all of a sameness to Dick—­a wilderness of rocks and jagged growths hemmed in by lowering ranges, always looking close, yet never growing any nearer.  The moon slanted back toward the west, losing its white radiance, and the gloom of the earlier evening began to creep into the washes and to darken under the mesas.  By and by Ladd entered an arroyo, and here the travelers turned and twisted with the meanderings of a dry stream bed.  At the head of a canyon they had to take once more to the rougher ground.  Always it led down, always it grew rougher, more rolling, with wider bare spaces, always the black ranges loomed close.

Gale became chilled to the bone, and his clothes were damp and cold.  His knees smarted from the wounds of the poisoned thorns, and his right hand was either swollen stiff or too numb to move.  Moreover, he was tiring.  The excitement, the long walk, the miles on miles of jolting trot—­these had wearied him.  Mercedes must be made of steel, he thought, to stand all that she had been subjected to and yet, when the stars were paling and dawn perhaps not far away, stay in the saddle.

So Dick Gale rode on, drowsier for each mile, and more and more giving the horse a choice of ground.  Sometimes a prod from a murderous spine roused Dick.  A grayness had blotted out the waning moon in the west and the clear, dark, starry sky overhead.  Once when Gale, thinking to fight his weariness, raised his head, he saw that one of the horses in the lead was riderless.  Ladd was carrying Mercedes.  Dick marveled that her collapse had not come sooner.  Another time, rousing himself again, he imagined they were now on a good hard road.

It seemed that hours passed, though he knew only little time had elapsed, when once more he threw off the spell of weariness.  He heard a dog bark.  Tall trees lined the open lane down which he was riding.  Presently in the gray gloom he saw low, square houses with flat roofs.  Ladd turned off to the left down another lane, gloomy between trees.  Every few rods there was one of the squat houses.  This lane opened into wider, lighter space.  The cold air bore a sweet perfume—­whether of flowers or fruit Dick could not tell.  Ladd rode on for perhaps a quarter of a mile, though it seemed interminably long to Dick.  A grove of trees loomed dark in the gray morning.  Ladd entered it and was lost in the shade.  Dick rode on among trees.  Presently he heard voices, and soon another house, low and flat like the others, but so long he could not see the farther end, stood up blacker than the trees.  As he dismounted, cramped and sore, he could scarcely stand.  Lash came alongside.  He spoke, and some one with a big, hearty voice replied to him.  Then it seemed to Dick that he was led into blackness like pitch, where, presently, he felt blankets thrown on him and then his drowsy faculties faded.