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178 them run along its very minute arms "at the rate of 9 or 10 miles a second! He was looking from Windsor across a gulf in space about nine hundred millions of miles in width. It was a romance of the heavens—one of many.

On ascertaining that his great telescope was not required for these observations on the ring and moons of Saturn, he "made ten new object specula and fourteen small plain ones for his 7-feet reflector, having already found that the maximum of distinctness might be much easier obtained than where large apertures are concerned." During his long-continued watch of Saturn he saw sometimes a northern belt on the body of the planet, sometimes two belts at the equator. In a couple of days the entry in his journal became "a bright belt over a dark one"; and, nine days later, "one dark and one very faint white belt." The last entry he quotes in 1790 is, "The bright belt close to the ring and two dark equatorial belts." These belts would be about one hundred thousand miles in length: what were they? Similar belts or bands had long been seen and studied on the planet Jupiter. It was agreed among observers that they were probably due to cloudy masses floating in Jupiter's atmosphere. If the same explanation hold for the belts of Saturn, the changes, seen on them by Herschel, would be explained by "a very considerable atmosphere," in which they take place. He not only adopted this conclusion, but confirmed it by another observation. When the two nearest of the moons—the two he discovered in 1789—came, in their progress round the planet, to the edge of the disc, they did not disappear at once, but continued "to