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186 groove or division of the ring," while it ceases to be a fanciful, becomes also an unnecessary conception.

Such are the main features of the romance of Saturn since Herschel began his study of it one hundred and twenty-five years ago. In the hundred and twenty-five years that preceded, there had also been mystery and romance about the planet and his ring. All the riddles presented by this system have not been yet read, and it is likely that, when improvements in telescopes or observation enable man to read the riddles that face him to-day, they will raise new riddles and give birth to other romances for the amazement or delight of future ages. On one point science is still in doubt. Does the fifth satellite of Saturn, like our moon, always show the same face to the planet, or, in other words, turn on its axis in the same time that it takes to revolve round him? Herschel believed he had proved, or almost proved, that it "turns once on its axis, exactly in the time it performs one revolution round its primary planet."

It was only fitting that the discoverer of Uranus should pay special attention to that planet: but five or six years elapsed before his patient watchfulness was crowned with any success. Unlike Jupiter and Saturn, the light of Uranus is very faint. He does not invite pursuit; he flies from it into darkness: and the light of his moons is fainter still. Herschel suspected, perhaps hoped, that if he searched for satellites he would find them. And so he did. On January 11, 1787, he saw "some very faint stars" near the planet, "whose places he noted down with great care." Next evening two of them were missing. As the haziness, that was about, might have caused their disappearance, he noted