I have forgotten old Abdul Dori, but he did not make a long stay on board. I have already mentioned that I suspected him of evil designs in taking service with us. He got me to advance him a pretty round sum on the voyage to Massina, which he said he owed to one of his countrymen, and desired to repay before he entered upon a venture so full of danger. As soon as the sly rogue had gained his end, he changed his tactics. From Sego, according to him, the voyage would be comparatively easy. His debt paid, he attempted to terrify my coolies, telling them the most ridiculous tales about the ferocity of the Tuaregs, and giving the most discouraging account of the rapids, which in the end we unfortunately found partly true. He soon discovered he was wasting his time. My men came of their own accord, and reported that Abdul was trying to dishearten them. I soon made him understand I would not stand that kind of thing. Seeing the failure of these manœuvres, and in no way anxious to remain with us, he shammed sickness, pretending to be attacked with dysentery. The doctor soon discovered the trick, and I told him that, ill or well, he would have to follow me. His plan having miscarried, he set about making himself really ill, and lay down to sleep without any covering on the chilliest nights. At this game, if he did not procure the dysentery of his dreams, he at least contracted inflammation of both lungs, which developed the very day of our departure. He remained two days longer with us; then really seriously ill, he became delirious. Moved with pity, I decided to send him back to Timbuktu in a canoe hired at the village of Burrem. I don’t know what became of him, but I advise those who may come across him hereafter, and are deceived by his honeyed words and ways, to beware of him. As far as we are concerned, I consider it a blessing that his cowardice overcame the desire for doing evil. He might have proved a great source of danger, especially at Say, his native place, where he would have aided and abetted our enemies. The first and most important object of the expedition was to trace as correctly as possible the course of the river which we had to follow. For this purpose I had observing instruments of very accurate construction made for each barge, which would afford us the means of making a triangulation of the river _en route_. Two barges were to coast along the banks, while the third kept in the deep channel. We tried this plan on January 23, the first day on which we navigated an almost unknown region. It was soon found impracticable. By evening we had gone less than four and a half miles. At this rate, counting necessary stoppages, it would take a year to reach the mouth of the river. We therefore adopted the following plan: the _Davoust_ followed the left bank; the _Aube_ the right one while on surveying duty, the two barges frequently taking their places.