y to warn our party.

CHAPTER XXIII.

A RIDE FOR LIFE.

'Moncrieff!' I cried, as soon as I got within hail, 'the Indians will be
on us in less than half an hour!'

'Then, boy,' replied Moncrieff, 'call in your brothers and the men; they
cannot hold the dune. We must fight them here, if it be fighting they
mean. Hurry back, I have something to show you.'

We had all returned in less than ten minutes. Greatly to our astonishment,
we found no one in the pit now, but we heard voices beneath, and I hurried
in and down.

They had found a cave; whether natural or not we could not at present say.
At one side lay a heap of mouldering bones, in the opposite corner a huge
wooden chest. Moncrieff had improvised a torch, and surely Aladdin in his
cave could not have been more astonished at what he saw than we were now!
The smoky light fell on the golden gleam of nuggets! Yes, there they were,
of all shapes and sizes. Moncrieff plunged his hand to the bottom of the
box and stirred them up as he might have done roots or beans.

This, then, was the secret the ruin had held so long--the mystery of the
giant ombu-tree.

That the Indians in some way or other had got scent of this treasure was
evident, and as these wandering savages care little if anything for gold
on their own account, it was equally evident that some white man--himself
not caring to take the lead or even appear--was hounding them on to find
it, with the promise doubtless of a handsome reward.

Not a moment was there to be lost now. The treasure must be removed. An
attempt was first made to lift the chest bodily. This was found to be
impossible owing to the decayed condition of the wood. The grain-sacks,
therefore, which formed a portion of the Gaucho's mule-trappings, were
requisitioned, and in a very short time every gold nugget was carried out
and placed in safety in a corner of our principal room in the
hunting-box.

The beasts were placed for safety in another room of the ruin, a trench
being dug before the door, which could be commanded from one of our
windows.

'How many horsemen did you count?' said Moncrieff to me.

'As near as I could judge,' I replied, 'there must be fifty.'

'Yes, there may be a swarm more. One of you boys must ride to-night to the
_estancia_ and get assistance. Who volunteers?'

'I do,' said Dugald at once.

'Then it will be well to start without delay before we are surrounded.
See, it is already dusk, and we may ex