The globe of Saturn, as already shown, casts a shadow on the rings, which, according to the position of the planet in its orbit, either extends across their whole breadth, or covers only a part of their surface. The shadow on the rings rising in the east after sunset, ascends to the culminating point of their arcs in the sky, in 2h. 34m., and as rapidly descends on the western horizon, to disappear with sunrise. This shadow, when projected on the rings in the sky, must be hardly distinguishable from the dark background of the heavens, except from the absence of stars in the regions which it occupies. It must appear as a large dark gap, separating the rings into two parts, and constantly moving from east to west. Possibly the refraction of the solar rays, in passing through Saturn's atmosphere, may cast some colored light on the rings, similar to that observed on the Moon during its eclipses. An observer on the rings would behold phenomena still more curious, a long day of 14¾ years being followed by a long night of 14¾ years. The long days of Saturn's rings are, however, diversified by numerous eclipses of the Sun, which regularly occur every 10¼ hours; the phenomenon being due to the interposition of the globe of Saturn between the rings and the Sun. These eclipses produce partial obscurations of their surface, lasting from 1½ to 2 hours at a time. Although the surface of the rings never receives direct sunlight during their long nights, yet they are not plunged all the time in total darkness, as they receive some reflected light from that part of the globe of Saturn which is illuminated by the Sun. To the supposed observer on the rings, during every 10¼ hours, the immense globe would exhibit continually changing phases. At first he would see a point of light rapidly ascending from the horizon, and appearing under the form of a half crescent of considerable radius; 5⅛ hours later, the crescent having gradually increased, would appear as a half circle, covering ⅛ of the visible heavens, its surface being more than 20,000 times as large as the surface of the Moon. Upon this brilliantly illuminated semi-circle would be projected the shadows of the rings, appearing as black belts separated by a narrow luminous band.