The cloud of dust got bigger and of a more distinct brown. Objects such as trees, which at one time stood out in front of it, were hidden one after another, till it spread out like heavy brown smoke from a damp fire. The air was very clear and still. All at once Sax gripped his friend's arm. He had heard a sound—a sound which was like his own native tongue to the drover's son—the crack of a stock-whip.
"I'm sure I heard a whip," he exclaimed excitedly. "I'm dead sure I did. Hark!"
Both boys sprang to their feet and listened intently. From out that advancing mass of brown dust sounds could be heard. At first they were just a confused murmur, a sort of deep grumbling very far away; but now and again came a sharper sound, half like the crack of a pistol and half like two flat boards being banged together.
"Yes. I'm sure of it. I'm sure of it. It's whips. I bet you it's whips. And that dust is kicked up by cattle. I know it is. Oh, Boofy, Boofy! P'raps it's my father."
"Let's go and meet him," suggested Vaughan, and the boy would have started out right away to meet the cattle if his friend had not prevented him. Sax had never seen a mob of bush cattle, at least not that he could remember, though his father had often carried him on the pommel of his saddle when he was a tiny baby. But he knew instinctively that it would be dangerous to face wild cattle on foot.
"Let's wait and see what happens," he said. "They won't be long."
The noise had now increased to the continuous rumbling bellow of a great mob of restless cattle. Already the shouts of men could be heard, and the cracks of whips came very sharp and clear. Dim forms could be seen for a moment now and again on the outskirts of the cloud of dust, as mounted men wheeled here and there and everywhere in their efforts to keep the cattle together. The animals had never seen a town before, and were frightened at the glitter of iron roofs in the sun.
Suddenly a figure on a horse shot out in front and cantered ahead. The boys became tense with excitement. Was it Mr. Stobart? At first they could not distinguish him except that he rode a grey horse and sat it with the perfect ease of a Central Australian. The animal did not want to leave its companions and started to "play up". But nothing it could do made any difference to the superb rider; he just sat as if he were part of the horse, as if he were indeed its brain, forcing it to obey his will. When he came past the little hill where the lads were standing he was about a hundred yards away from them, and they could see him clearly.
"Is it, Sax?" asked Vaughan excitedly. "Is it your pater?"
The drover's son shook his head. "No chance," he said sadly. "My father's taller than that man. But can't he just ride, Boof?"