His long head was thrust out almost straight, and his great body fairly skimmed the earth.

But the Mexicans hung on with grim tenacity.

Their ponies were tough and enduring, and, spread out like the arc of a bow, they continually profited by some divergence that Old Jack made from the straight line.
Aware of this danger Ned himself, nevertheless, was unable to tell whether the horse was going in a direct course, and he let him have his head.
"Crack!" went a musket, and a bullet sang past Ned's face.

It grazed Old Jack's ear, drawing blood.

The horse uttered an angry snort and fairly leaped forward.