That box was opened, and a morsel of paper fell from it, on which Dick Sand read these few words:

"Assassinated--robbed by my guide, Negoro--3d December, 1871--here--120 miles from the coast--Dingo!--with me!

"S. VERNON."

The note told everything. Samuel Vernon set out with his dog, Dingo, to explore the center of Africa, guided by Negoro. The money which he carried had excited the wretch's cupidity, and he resolved to take possession of it. The French traveler, arrived at this point of the Congo's banks, had established his camp in this hut. There he was mortally wounded, robbed, abandoned. The murder accomplished, no doubt Negoro took to flight, and it was then that he fell into the hands of the Portuguese. Recognized as one of the trader Alvez's agents, conducted to Saint Paul de Loanda, he was condemned to finish his days in one of the penitentiaries of the colony. We know that he succeeded in escaping, in reaching New Zealand, and how he embarked on the "Pilgrim" to the misfortune of those who had taken passage on it. But what happened after the crime? Nothing but what was easy to understand! The unfortunate Vernon, before dying, had evidently had time to write the note which, with the date and the motive of the assassination, gave the name of the assassin. This note he had shut up in that box where, doubtless, the stolen money was, and, in a last effort, his bloody finger had traced like an epitaph the initials of his name. Before those two red letters, Dingo must have remained for many days! He had learned to know them! He could no longer forget them! Then, returned to the coast, the dog had been picked up by the captain of the "Waldeck," and finally, on board the "Pilgrim," found itself again with Negoro. During this time, the bones of the traveler were whitening in the depths of this lost forest of Central Africa, and he no longer lived except in the remembrance of his dog.

Yes, such must have been the way the events had happened. As Dick Sand and Hercules prepared to give a Christian burial to the remains of Samuel Yernon, Dingo, this time giving a howl of rage, dashed out of the hut.

Almost at once horrible cries were heard at a short distance. Evidently a man was struggling with the powerful animal.

Hercules did what Dingo had done. In his turn he sprang out of the hut, and Dick Sand, Mrs. Weldon, Jack, Benedict, following his steps, saw him throw himself on a man, who fell to the ground, held at the neck by the dog's formidable teeth.

It was Negoro.

In going to the mouth of the Zaire, so as to embark for America, this rascal, leaving his escort behind, had come to the very place where he had assassinated the traveler who had trusted himself to him.

But there was a reason for it, and all understood it when they perceived some handfuls of French gold which glittered in a recently-dug hole at the foot of a tree. So it was evident that after the murder, and before falling into the hands of the Portuguese, Negoro had hidden the product of his crime, with the intention of returning some day to get it. He was going to take possession of this gold when Dingo scented him and sprang at his throat. The wretch, surprised, had drawn his cutlass and struck the dog at the moment when Hercules threw himself on him, crying:

"Ah, villain! I am going to strangle you at last!"

There was nothing more to do. The Portuguese gave no sign of life, struck, it maybe said, by divine justice, and on the very spot where the crime had been committed. But the faithful dog had received a mortal blow, and dragging itself to the hut, it came to die there--where Samuel Vernon had died.

Hercules buried deep the traveler's remains, and Dingo, lamented by all, was put in the same grave as its master.

Negoro was no more, but the natives who accompanied him from Kazounde could not be far away. On not seeing him return, they would certainly seek him along the river. This was a very serious danger.

Dick Sand and Mrs. Weldon took counsel as to what they should do, and do without losing an instant.