At once Hercules, Bat, Austin, and Dick Sand took their way to the mouth of the river.

But, arrived at the bank, they neither saw nor heard anything.  Dingo now was silent.

Dick Sand and the blacks returned to the grotto.

The going to sleep was organized as well as possible.  Each of the blacks prepared himself to watch in turn outside.  But Mrs. Weldon, uneasy, could not sleep.  It seemed to her that this land so ardently desired did not give her what she had been led to hope for, security for hers, and rest for herself.

* * * * *

CHAPTER XV.

HARRIS.

The next day, April 7th, Austin, who was on guard at sunrise, saw Dingo run barking to the little river.  Almost immediately Mrs. Weldon, Dick Sand and the blacks came out of the grotto.

Decidedly there was something there.

“Dingo has scented a living creature, man or beast,” said the novice.

“At all events it was not Negoro,” observed Tom, “for Dingo would bark with fury.”

“If it is not Negoro, where can he be?” asked Mrs. Weldon, giving Dick Sand a look which was only understood by him; “and if it is not he, who, then, is it?”

“We are going to see, Mrs. Weldon,” replied the novice.  Then, addressing Bat, Austin, and Hercules, “Arm yourselves, my friends, and come!”

Each of the blacks took a gun and a cutlass, as Dick Sand had done.  A cartridge was slipped into the breech of the Remingtons, and, thus armed, all four went to the bank of the river.

Mrs. Weldon, Tom, and Acteon remained at the entrance of the grotto, where little Jack and Nan still rested by themselves.

The sun was then rising.  His rays, intercepted by the high mountains in the east, did not reach the cliff directly; but as far as the western horizon, the sea sparkled under the first fires of day.

Dick Sand and his companions followed the strand of the shore, the curve of which joined the mouth of the river.

There Dingo, motionless, and as if on guard, was continually barking.

It was evident that he saw or scented some native.

And, in fact, it was no longer against Negoro, against its enemy on board the ship, that the dog had a grudge this time.

At that moment a man turned the last plane of the cliff.  He advanced prudently to the strand, and, by his familiar gestures, he sought to calm Dingo.  They saw that he did not care to face the anger of the vigorous animal.

“It is not Negoro!” said Hercules.

“We cannot lose by the change,” replied Bat.

“No,” said the novice.  “It is probably some native, who will spare us the ennui of a separation.  We are at last going to know exactly where we are.”

And all four, putting their guns back on their shoulders, went rapidly toward the unknown.