| In 1879, 9h. 55m. 33·9s. |
| In 1886, 9h. 55m. 40·6s. |
| In 1891, 9h. 55m. 41·7s. |
Since 1891 this tendency seems to have ceased, while the spot has been gradually fading away. Generally speaking, we may say that the equatorial regions rotate in about 9h. 50m. 20s., and the temperate zones in about 9h. 55m. 40s. Remarkable exceptions are occasionally met with. Some small black spots in north latitude 22°, which broke out in 1880 and again in 1891, rotated in 9h. 48m. to 9h. 49-1⁄2m. It may, therefore, be regarded as certain that the globe of Jupiter, so far as we can see it, is not a solid body. It consists, on the exterior at all events, of clouds and vaporous masses, which seem to be agitated by storms of the utmost intensity, if we are to judge from the ceaseless changes of the planet's surface.
PLATE XI.
Feb. 2nd. Feb. 4th.
Feb. 12th. Feb. 28th.
THE PLANET JUPITER.
1897.
Fig. 57.—The Occultation of Jupiter (1).