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never can). We notice first the dark Cassini division, separating the rings into two, an inner and an outer one, the latter being the narrower. Then, on the outer ring, we see the faint and grey Encke division, which is much
Fig. 39.—Perpendicular View of the Rings of Saturn. less marked and much harder to see than the other. Passing to the inner ring, the latter shades off gradually on the inner edge, where there is a grey border called the "crape ring." This was first described by Bond, of the Harvard Observatory, and was long supposed to be a separate and distinct ring. But careful observation shows that such is not the case. The crape ring joins on to the ring outside of it, and the latter merely fades away into the other.

The rings of Saturn are inclined about twenty-seven degrees to the plane of its orbit, and they keep the same direction in space as the planet revolves round the sun. The effect of this will be seen by the figure, which shows the orbit of the planet round the sun in perspective. When the planet is at A the sun shines on the north (upper) side of the ring. Seven years later, when the