_Dörfel Mountains._ Visible on the Moon’s S.S.E. limb. They exhibit three peaks, which, on the authority of Schröter, rise to more than 26,000 feet above the average level of the limb. The loftiest mountains on the Earth are in the Himalayas—a range of immense extent to the N. of India. The three highest peaks are Mount Everest (29,002 feet), Kunchinjinga (28,156 feet), and Dhawalagiri (28,000 feet). The only lunar mountain more elevated than these is that of the Leibnitz range, which, as we have already stated, ascends to fully 30,000 feet. [Illustration: Fig. 28. Aristarchus and Herodotus at sunrise. 1884, Jan. 9, 8^h 30^m to 10^h 30^m. (T. Gwyn Elger.)] _Apennines._ A vast chain of mountains, extending over more than 450 miles of the lunar surface. _Huygens_ is the most elevated peak, rising to more than 18,000 feet, and on its summit it shows a small crater. There are several other very lofty peaks in this range. The Sun rises upon the westerly region of these mountains at the time of first quarter, and the peaks and ridges, with their contrasting shadows, create a gorgeous effect just within, and projecting into the darkness beyond, the terminator. There is an immense amount of detail to be studied here, and much of it is within the reach of small instruments. As the lunar mountains and craters are best seen near the terminator, it may be useful to give a table of objects thus favourably placed between the times of new and full Moon. The summary may assist the student, though it does not aim at exactness, only even days being given. _Objects near the Terminator._ Moon’s age in days. 2 Mare Crisium, Messala, Sunrise on the Mare Humboldtianum, Langrenus, Vendelinus, Condorcet, Hansen, Gauss(β), Hahn, Berosus. 3(α) Craters in Mare Crisium, Taruntius, Picard, Fraunhofer, Vega, Pontécoulant, Cleomedes(γ), Furnerius, Petavius, Endymion, Messier(δ), Vlacq. 4 Mare Nectaris, Macrobius(ε), Proclus, Sunrise on Fracastorius, Rheita and Metius with the intervening valley, Guttemberg, Colombo, Santbech, Mountainous region W. of Mare Serenitatis, Hercules, Atlas. 5 Palus Somnii, Plana, Capella, Isidorus, Polybius, Piccolomini, Vitruvius, Littrow, Fabricius, Posidonius, LeMonnier, Theophilus, Cyrillus, Catharina, Hommel. 6 Tacitus, Maurolycus, Barocius, Dionysius(ζ), Sosigenes, Abulfeda, Descartes, Almamon, Gemma Frisius, Plinius, Ross, Arago, Delambre, Aristoteles, Eudoxus, Julius Cæsar, Linné, Menelaus. α The objects for observation when the Moon’s age is from 2 to 4 days may be suitably re-examined a few days after the full. β An extensive walled plain, 110 miles in length. γ A large walled plain containing a small crater, Cleomedes A. δ A curious double crater, with comet-like rays crossing the Mare Fœcunditatis.