one
side by the angle of the sun, in cheerful, jogging fraternity. Prather
and Nogales had again become only a speck.

"Do you think that they are out of the sand?" asked Jack.

"Very near," Firio answered.

"Their ponies had a whole night's rest--we must not forget that," said
Jack; "and they must be in a hurry, for certainly Nogales had sense
enough to rest over noon."

"_Quien sabe_!" answered Firio. "But we catch them--_si, si_!"

Leading the way, Firio turned toward the eastern range until he came to a
narrow tongue of shale almost as hard to the hoofs as asphalt, that ran
like a shoal across that sea of sand. Rest had given the great equine
trio renewed life. P.D., reduced in rank to second place, could not think
of allowing more than a foot between his muzzle and the tail of Wrath of
God, who was bound to make up the time he had lost in pursuit of the
horizon. Another hypothesis of Jack's as to the cause of Wrath of God's
melancholy was that solemn Covenanter's inability to get any nearer to
the edge of the earth. Once he could poke his nose through the blue
curtain and see what was on the other side, the satisfaction of his
eternal curiosity might have made him a rollicking comedian. As for Jag
Ear, his baton was once more conducting his orchestra in spirited tempo.
He, who was nearest of all three in heart to Firio, might well have been
saying to himself: "I knew! I knew we were not going through the sand!
Firio and I knew!"

So rapidly were they gaining that, when past the sand and they turned
back westward, it was only a question of half an hour or so to come up
with Prather and Nogales. Nogales had been riding ahead; but now Prather,
after gazing over his shoulder for some time at his pursuers, took the
lead. He was urging his horse as if he would avoid being overtaken.
Evidently Nogales did not share that desire, for he let Prather go on
alone. But Prather's horse was too tired after its effort in the sand and
he halted and waited until Nogales, at a slow walk, closed up the gap
between them, when they proceeded at their old, weary gait.

As Jack and Firio came within hailing distance, both Prather and Nogales
glanced at them sharply; but no word was spoken on either side. The
absence of any call between these isolated voyagers of the desert sea was
strangely unlike the average desert meeting. Prather and Nogales did not
look back again, not even when Jack and Firio were very near. A neigh by
P.D.,