This route must really present, in some parts, for many hours together, an ocean of sand; as, I think, it is described in the Itinerary procured by Davis. To-day the footprints of the giraffe have entirely disappeared. In summer it must be very difficult for large caravans to obtain water from this well, for our people were full half a day filling four or five skins. What a blessing, nevertheless, is the existence of the Chidugula, for there is no water for three days farther. The boys killed this morning a jerboah, or what the Germans call a jumping mouse. I saw one yesterday, jumping before my camel's feet. There are a great number here. This jerboah is of a different colour from those I have seen in Tunis; being white all over the lower part of the body and neck, straw-coloured on the top of the head and along the back; whilst those in Tunis are nearly of the same colour as ordinary mice. This species is also small, three inches and a-half long, and the tail is double the length of the body. The hind legs are nearly as long as the body, and the fore legs not half an inch. Near the tip of the tail there is an inch of black. Many young jerboahs were caught, all of the same description. The Haussa people call it a mouse, but have besides a special name. We are now about the middle of the Sahara, including the radii of the western and northern coasts, and we here find an immense plateau, stretching many days north and south, east and west. So far Le Brun's conjecture is right, that the central parts of Africa are plateaux, or one vast plateau. But more of this hereafter. This plateau extends to the Bornou route, and how much further east is yet to be ascertained. In the west we yet also want information. North and south it extends along the territory of Aheer some eight days, or about one hundred and sixty miles. Overweg reckons the height of the plateau, above the level of the sea, at some fifteen hundred feet. _31st._--The last day of the year! One year gone in Africa this tour! How many more are to pass? Alas! who can tell?--We came to-day nine hours, always south, over a perfect desert-plain, mostly sandy. A cold north-east wind was blowing all the day. The people dread it as death itself; as well they may, for they are nearly naked. Their Soudan cotton clothes afford them little or no protection against such a bleak north-easter. Europeans are astonished to see these people shivering with cold in this bleak weather, and forget that they themselves are well clothed. This remark is very applicable to the northern coast, where hundreds of the poor are seen shivering, with only a thin blanket thrown around them in the coldest day of winter. When they see a European well covered with tight cloth clothes, and flannel underneath, they may well call out _sega_, "cold," as they often do; and we are ready to laugh, and forget they are naked.