“Menelaus?” exclaimed my friend. “Ah, then Riccioli did not confine his favoritism to the astronomers and philosophers in putting their names in the moon. Menelaus, if I remember my classical reading correctly, was the husband of Helen of Troy.” “Yes, the brother of Agamemnon himself. You must admit that Riccioli occasionally felt his imagination a little awakened. He was not altogether destitute of the spirit of poetry.” “But did he also put Helen in the moon?” “I am sorry to say that he did not. It would have been a very suitable abode for her. However, if you like, you may recognize Helen in the Moon Maiden herself.” “Thank you, that will be, indeed, an unexpected pleasure.” “Meanwhile allow me to point out to you that there is a curious light streak, very faintly shown in the photograph, which crosses the _Mare Serenitatis_ from Menelaus to the opposite shore, and reappears more distinctly, on the lighter-colored plain toward the north. This streak comes all the way from a great ring mountain named Tycho in the southern part of the moon. It is more than 2,000 miles long, and is one of the greatest mysteries of the lunar world. Tycho, which lies just on the sunrise line, is not well seen in this photograph. It has a great number of these strange streaks or rays proceeding from it in all directions. We shall study them in one of the photographs which are to come. One word in regard to the plain north of the _Mare Serenitatis_ of which I have just spoken. It, too, has a name that is calculated to appeal to your lively imagination. It is called the _Lacus Somniorum_, which if my knowledge of Latin is correct, means ‘Lake of the Sleepers.’” “Then your old friend Riccioli certainly did not bestow the appellation.” “No, it was one of his more fanciful, or, if you prefer, more poetical predecessors, perhaps the same who imagined the ‘Marsh of a Dream.’” “Oh, that gives me another reason to think of him with admiration and gratitude. He, at least, had a soul that rose above mere prosaic facts.” “Perhaps. But do not think too lightly of the facts of the moon. After all the human mind must base itself upon the solid ground of fact. Without that we should become mere dreamers, and be suited only to inhabit your favorite ‘Marsh.’” “The other mountain ranges of which I have spoken,” I continued, “are faintly distinguishable eastward from the _Mare Serenitatis_. They are the Apennines, the Caucasus, and the Alps. But perhaps we had better turn at once to photograph No. 8 where they are much more clearly seen, because the sunrise there has advanced a couple of hundred miles farther east.” “But, dear me, how slowly the sun rises on the moon! Was this photograph taken a day later than the other?” [Illustration: NO. 8. AUGUST 31, 1903; MOON’S AGE 9.22 DAYS. ]