A man can hardly lift up his eyes towards the heavens without wonder and veneration, to see so many millions of radiant lights, and to observe their courses and revolutions, even without any respect to the common good of the Universe.--SENECA. CHAPTER X THE STARRY HEAVENS Many years ago I paid a visit to Naples, and ascended Vesuvius to see the sun rise from the top of the mountain. We went up to the Observatory in the evening and spent the night outside. The sky was clear; at our feet was the sea, and round the bay the lights of Naples formed a lovely semicircle. Far more beautiful, however, were the moon and the stars overhead; the moon throwing a silver path over the water, and the stars shining in that clear atmosphere with a brilliance which I shall never forget. For ages and ages past men have admired the same glorious spectacle, and yet neither the imagination of Man nor the genius of Poetry had risen to the truer and grander conceptions of the Heavens for which we are indebted to astronomical Science. The mechanical contrivances by which it was attempted to explain the movements of the heavenly bodies were clumsy and prosaic when compared with the great discovery of Newton. Ruskin is unjust I think when he says "Science teaches us that the clouds are a sleety mist; Art, that they are a golden throne." I should be the last to disparage the debt we owe to Art, but for our knowledge, and even more, for our appreciation, feeble as even yet it is, of the overwhelming grandeur of the Heavens, we are mainly indebted to Science. There is scarcely a form which the fancy of Man has not sometimes detected in the clouds,--chains of mountains, splendid cities, storms at sea, flights of birds, groups of animals, monsters of all kinds,--and our superstitious ancestors often terrified themselves by fantastic visions of arms and warriors and battles which they regarded as portents of coming calamities. There is hardly a day on which Clouds do not delight and surprise us by their forms and colours. They belong, however, to our Earth, and I must now pass on to the heavenly bodies. [Illustration: THE MOON. _To face page 377._] THE MOON The Moon is the nearest, and being the nearest, appears to us, with the single exception of the Sun, the largest, although it is in reality one of the smallest, of the heavenly bodies. Just as the Earth goes round the Sun, and the period of revolution constitutes a year, so the Moon goes round the Earth approximately in a period of one month. But while we turn on our axis every twenty-four hours, thus causing the alternation of light and darkness--day and night--the Moon takes a month to revolve on hers, so that she always presents the same, or very nearly the same, surface to us.