§ 524, 525. THE CLOUD REGION, ETC. 283 



the equator ; therefore we infer that this line of meeting extends 

 around the world. By the rainy seasons of the torrid zone, ex- 

 cept where it may be broken by the continents, we can trace the 

 declination of this cloud-ring, stretched like a girdle around our 

 planet, up and down the earth ; it travels after the sun up and 

 down the ocean, as from north to south and back. It is broader 

 than the belt of calms out of which it rises. As the air, with its 

 vapors, rises up in this calm belt and ascends, these vapors are 

 condensed into clouds, and this condensation is followed by a tur- 

 gid intumescence, which causes the clouds to overflow the calm 

 belt, as it were, both to the north and the south. The air flowing 

 off in the same direction assumes the character of winds that form 

 the upper currents that are counter (Plate I.) to the trade-winds. 

 These currents carry the clouds still farther to the north and south, 

 and thus make the cloud-ring broader. At least we infer such to 

 be the case, for the rains are found to extend out into the trade- 

 winds, and often to a considerable distance both to the north and 

 the south of the calm belt. 



524. Were this cloud-ring luminous, and could it be seen by an 

 Imagined appear- obscrvcr from ouc of thc plaucts, it would present to 

 ?SStolSstannbI ^"^i"^"^ ^^ nppearance not unlike the rings of Saturn 

 ^^'^^- do to us. Such an observer would remark that this 

 cloud-ring of the earth has a motion contrary to that of the axis of 

 our planet itself — that while the earth was revolving rapidly from 

 west to east, he would observe the cloud-ring to go slowly, but 

 only relatively, from east to west. As the winds which bring 

 this cloud- vapor to this region of calms rise up with it, the earth 

 is slipping from under them ; and thus the cloud-ring, though 

 really moving from west to east with the earth, goes relatively 

 slower than the earth, and would therefore appear to require a 

 longer time to complete a revolution. But, unlike the rings of 

 Saturn through the telescope, the outer surface, or the upper side 

 to us, of this cloud-ring would appear exceedingly jagged, rough, 

 and uneven. 



525. The rays of the sun, playing upon this peak and then upon 

 Thunder. that of thc uppcr cloud-surface, melt away one set 



of elevations and create another set of depressions. The whole 

 stratum is, it may be imagined, in the most turgid state ; it is in 

 continued throes when viewed from above; the heat which is 



