A GIANT PLANET. 97 



insignificant. During the year I860, a rift in one of 

 the Jovian cloud-belts behaved in such a way as to 

 demonstrate the startling fact that a hurricane was 

 raging over an extent of Jovian territory equalling the 

 whole surface of our earth, at a rate of fully 150 miles 

 per hour. It is not too much to say that a hurricane 

 of like velocity on our earth would destroy every 

 building in the territory over which it raged, would 

 uproot the mightiest forest trees, and would cause in 

 fact universal desolation. At sea no ship that man 

 ever made could withstand the fury of such a storm 

 for a single minute. And yet this tremendous Jovian 

 hurricane continued to rage with unabated fury for at 

 least six weeks, or for fully one hundred Jovian 

 days. 



But during the last two or three years a change of so 

 remarkable a nature has passed over Jupiter as to imply 

 the existence of forces even more energetic than those 

 at work in producing atmospheric changes. 



In the autumn of 1870, my friend Mr. Browning (the 

 eminent optician) called the attention of astronomers 

 to the fact that the great equatorial zone, usually, 

 as we have said, of a creamy white colour, had 

 assumed a decidedly orange tint. At the same time it 

 had become much less uniform in outline, and sundry 

 peculiarities in its appearance could be recognised, 

 which have been severally compared to portholes, pipe- 

 bowls and stems, oval mouldings, and other objects of 

 an uncelestial nature. Without entering into descrip- 

 tions which could only be rendered intelligible by 



E 



