The evenings, nights, and mornings were icy-cold, though the thermometer never fell below freezing-point. Our camels, taken aback by the novelty of the grass offered them, cropped it very sparsely; our provisions were giving out, and the rebels had fled before our arrival into exceptionally difficult mountainous tracts, where we could not dream of following them. In a word, in spite of the geographical interest there would have been in prolonging our stay on the summit of Emi Koussi, when the fourth day came we had to think about getting back to Yono. [Illustration: STEEP SLOPES ON THE FLANK OF EMI KOUSSI, TIBESTI] [Illustration: THE GREAT CLIFF, TIBESTI] [Illustration: NATURAL CISTERN OF DERSO AT THE FOOT OF EMI KOUSSI] [Illustration: THE CRATER OF EMI KOUSSI (3400 m.), TIBESTI] From this excursion on the highest peak of the highest mountain in the Sahara I brought away an abiding impression of wild magnificence, and most of all when one’s thoughts go back to the panorama of the Tibestian mountains. There may, I fear, be something of presumption in attempting even a short description; still, I will ask your permission to make a short extract from my diary on the day in question: “. . . Continuing our march northwards, we soon reach the foot of the cliffs of the northern wall, where, by a natural staircase, nearly 600 feet in height, one can reach the Tiribon pass, through which run the difficult paths that lead to Miski, Tozeur, and Goumeur. “In front of us the volcano slopes steeply downwards, leaving open to view the Tibestian massif with the endless succession of points of its serrated ridges outlined against the sky and stretching away out of sight. On our left the crater-wall loses itself in a confused mass of rocks, while on the right rise a number of sharp peaks, one of which seems to be the culminating point of this part of the ring of heights that shut in the volcano.