er. He opened his eyes at last and realized that
somebody was bending over him, but he was so sleepy that he did not
call out.

As soon as he saw that Sax was awake, the native held up his left hand,
so that the white boy could see it outlined against the pale night sky.
The two middle fingers were missing. It was the man who had already
done him more than one good turn.

Stobart sat up, prepared for anything which this black-fellow--who knew
the father, and seemed so devoted to the son--might suggest. The man
pointed down across the trampled sand towards the cattle-troughs. He
did it again and again, making little runs in that direction and coming
back at once, like a dog who wants its master to go in a certain
direction.

"All right, I'll come," whispered Sax at last, forgetting that the man
probably could not understand him. Sax had intended to go alone, but
when he stood up, Vaughan opened his eyes and asked sleepily: "What's
all the row about?"

"No row at all," whispered his companion. "That is, unless you make
it. There's something wrong somewhere and I'm going to have a look."

"So am I," responded Vaughan quickly, for the chance of an adventure
drove all sleep away from him. "So am I. You bet your life."

The silent native led the way, armed with a boomerang and a shield,
creeping from the shelter of one building to that of another, till they
were close to the troughs. The man held up his finger and listened.
There was a sound of running water. Sax recognized it as the
ball-valves of the troughs. There were four of them. Suddenly the
thought struck him: Why were they running? From where the three men
were standing the dark lines of the troughs could be seen even at
night, against the light-coloured sand, and it was clear that no stock
were drinking there. But if the valves were running it showed that the
troughs were empty, and the water must be flowing away somewhere. It
must be wasting.

The importance of water in the desert had already impressed itself upon
the white boys, and as soon as they realized that precious water was
running away in the sand, they rushed out from behind the shelter
towards the troughs. The armed native went with them.

There should have been a plug at the end of each trough. Somebody had
pulled these plugs out, and the water was gushing a full stream through
the four ball-valves and was running to waste over the sand. This had
apparently not been going on