his being so, the pony began to what is called "buck," that is to say,
instead of letting its back remain in an agreeable hollow curve, one
which seems to have been made by nature on purpose to hold a human
being, it curved its spine in the opposite direction, arching it as a
cat would, but of course in a modified way, and then began leaping up
from the earth in a series of buck jumps, all four hoofs from the ground
at once.

Still, in spite of this being the most difficult form of horse trouble
to master, Bart kept his seat. He was jerked about a great deal, but he
had been long used to riding restive horses, and he sat there as coolly
as if in a chair.

Then the Indian pony uttered a few shrill snorts and squeaks, throwing
up its head, and finally turning round, first on one side then upon the
other, it tried to bite its rider's legs--attacks which Bart met by a
series of sharp blows, given with the lariat that was coiled by the
horse's neck.

These pranks went on for a few minutes, the Indian looking smilingly on
the while, till, seeing that Bart was not to be dislodged, the pony
began to back and finally lay down.

This of course dismounted the rider, and with a snort of triumph the
pony sprang to its feet again, evidently meaning to bound off after
Black Boy and enjoy a turn of freedom.

The pony had reckoned without its rider, for Bart was too old at such
matters to leave his grasp of the rein, and the Indian cob's first
knowledge of its mistake was given by a sharp check to its under jaw,
round which the horse-hair rope was twitched, the next by finding its
rider back in his old place where he had leaped as lightly as could be.

The Indian gave an approving grunt, and uttering what was quite a sigh,
the pony resigned itself to its fate, and obeying the touch of Bart's
heel, went off at a fine springing gallop.

It was a long chase and an arduous one, for Black Boy seemed to laugh to
scorn all attempts at capture--of course these were horse-laughs--and
led his pursuers a tremendous run; and had it not been for his master,
late as he was in the field, the cob would not have been captured that
night. As it was, Bart went off at speed, setting at defiance
prairie-dogs' burrows, and other holes that might be in his way, and at
last he contrived to cut off a corner so as to get nearer to his nag,
when, taking the rein beneath his leg, he placed both hands to his mouth
and uttered a long shrill cry.

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