THE PLANET JUPITER.

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occasionally only one was visible ; while, in general, two (oneon each side of the equator), or three; and sometimes four,five, six, or even seven, were seen; or, as has happened morethan once, the whole surface nearly as far as the poles hasbeen traversed by a succession of numerous and rather faintparallel markings, alternately darker and lighter.

A continuous and careful course of observation has shownthat some of the principal features of these belts frequentlyremain comparatively constant for weeks or months together.At other times they are disturbed by changes so rapid, thatthe only phenomenon with which they seem to be in any wisecomparable (and even that is on a vastly smaller scale), isthe extraordinarily rapid formation of a stratum of cloud, bywhich we occasionally see a clear blue sky entirely overcastfrom one horizon to the opposite in the course of a few briefmoments.

In the various belts, unusually dark spots, or unusuallybright spots, of various degrees of magnitude, may also oftenbe watched, while they are carried, rapidly round by theplanet’s rotation. Of these, small bright spots are upon thewhole the most rare; but they are, if carefully followed andstudied, as some have been which have recently appeared inthe midst of the equatoreal regions of the planet, perhaps morefull of interest and instruction than any others.

"We much regret that the space at our disposal does notallow us to enter upon anything like an exhaustive description,or discussion, of the never-ending variety in the appearance ofthe belts and spots of Jnpiter. We must perforce be contentwith a brief mention of some of the more interesting observa-tions of recent date, and refer our readers for further informa-tion to the Records of the Royal Astronomical Society , and tomany interesting articles which have appeared in the Obser-vatory , the Astronomical Register, and other scientific publi-cations.

In Fig . LXVII., we have an attempt to reproduce a verybeautiful drawing of the planet made by Mr. De La Rue, onOctober 2oth, 18ofi. Although the woodcut is certainly tooharsh in its outlines, and does not very well represent the