whirring of wings,
a burst of screaming, and a flock of birds flew over their heads, with
the plumage looking in the morning light as white as snow.

"Cockatoos?" cried Nic wildly.

"Yes," said his father, smiling at the boy's enthusiasm over what was
one of the commonest sights to him. "I have seen them before. Now
then, breakfast for our prisoners. I shall be glad when we can let
those dogs run free."

CHAPTER ELEVEN.

HOW TO RIDE.

"Poor old chaps!" cried Nic, as the dogs leaped and tore about when he
left them, each straining at its collar with starting eyes, and uttering
in unison a piteous howl which could only bear one interpretation:

"Oh, I say, it's too bad! Don't keep us tied up like this."

Nic was ready to pity them again a few minutes after, when, in obedience
to a shout and the crack of a whip, the sleek oxen, which stood yoked,
blinking and chewing their cuds, started for the day's march, tightening
the dogs' chains. Then the collies sulkily allowed themselves to be
dragged along by the neck for a few yards before, feeling that
resistance was in vain, they gave up and began to start barking in
protest, running forward as far as their chains would allow under the
waggon, as if longing to get at the oxen's heels, and finally, after a
loud yelp or two at one another, settling down to their prisoners'
tramp.

The horses were bridled and saddled after Nic had taken his gun from
where it had been stood against a tree. The two men were in front of
the team, with Brookes talking loudly and unpleasantly to his fellow;
and the black was following behind the dogs, with his spear over his
shoulder, at times lowering it to stir the dogs up behind whenever they
showed an inclination to hang back.

This happened a minute after the start had been made, and Nic burst out
laughing.

"I say, father, look at that," he cried.

"I was looking, my boy," said the doctor. "That fellow seems to
understand the dogs better than we do."

For, at the first touch of the spear, one of the collies turned round
sharply, and barked; then the other received a prod--from the blunt end
in both cases--and the bark uttered was exactly like a protesting
"_Don't_!"

But the black, who was safe from attack as long as he kept beyond the
reach of the chain, continued to administer pokes, with the result that
the dogs trotted on as far as they could, looking back the while and
uttering threatening barks and growls.

Bu