The islands--the next feature on the Moon's surface--are exceedingly numerous. Generally oblong or circular in shape and almost as regular in outline as if drawn with a compass, they form vast archipelagoes like the famous group lying between Greece and Asia Minor, which mythology has made the scene of her earliest and most charming legends. As we gaze at them, the names of Naxos, Tenedos, Milo, and Carpathos rise up before our mind's eye, and we begin looking around for the Trojan fleet and Jason's Argo. This, at least, was Ardan's idea, and at first his eyes would see nothing on the map but a Grecian archipelago. But his companions, sound practical men, and therefore totally devoid of sentiment, were reminded by these rugged coasts of the beetling cliffs of New Brunswick and Nova Scotia; so that, where the Frenchman saw the tracks of ancient heroes, the Americans saw only commodious shipping points and favorable sites for trading posts--all, of course, in the purest interest of lunar commerce and industry. To end our hasty sketch of the continental portion of the Moon, we must say a few words regarding her orthography or mountain systems. With a fair telescope you can distinguish very readily her mountain chains, her isolated mountains, her circuses or ring formations, and her rills, cracks and radiating streaks. The character of the whole lunar relief is comprised in these divisions. It is a surface prodigiously reticulated, upheaved and depressed, apparently without the slightest order or system. It is a vast Switzerland, an enormous Norway, where everything is the result of direct plutonic action. This surface, so rugged, craggy and wrinkled, seems to be the result of successive contractions of the crust, at an early period of the planet's existence. The examination of the lunar disc is therefore highly favorable for the study of the great geological phenomena of our own globe. As certain astronomers have remarked, the Moon's surface, though older than the Earth's, has remained younger. That is, it has undergone less change. No water has broken through its rugged elevations, filled up its scowling cavities, and by incessant action tended continuously to the production of a general level. No atmosphere, by its disintegrating, decomposing influence has softened off the rugged features of the plutonic mountains. Volcanic action alone, unaffected by either aqueous or atmospheric forces, can here be seen in all its glory. In other words the Moon looks now as our Earth did endless ages ago, when "she was void and empty and when darkness sat upon the face of the deep;" eons of ages ago, long before the tides of the ocean and the winds of the atmosphere had begun to strew her rough surface with sand and clay, rock and coal, forest and meadow, gradually preparing it, according to the laws of our beneficent Creator, to be at last the pleasant though the temporary abode of Man!