MAJOR PLANETS. 



241 



the clouds which float upon our atmosphere. It is evident that such an effect 

 Would be more strongly marked in proportion as the energy of the causes pro- > 

 ducino it would be increased. 



In the case of the earth, the surface at the equator is moved by the diurnal 

 motion at the rate of about a thousand miles an hour ; and the sun, at different 

 seasons of the year, departs from the equator on either side to a distance of ' 

 twenty-three and a half degrees. If the velocity of the surface of the equator 

 were to become ten or twenty times greater, and the sun, instead of departing '! 

 from it twenty-three degrees, were constantly vertical to it, then we might ex- i f 

 pect to have atmospheric currents parallel to the line much more energetic, s 

 constant, and regular. 



But in the case of JUPITER, it will be easily seen that the causes producing 

 such currents are far more energetic than on the earth. Instead of revolving 

 in twenty-four hours, Jupiter revolves in ten hours. If, then, the globe of Ju- 

 piter were equal to that of the earth, the velocity of his surface at the line 

 would be greater than in the case of the earth in the proportion of two and a 

 half to one. The velocity of his surface would, in fact, be about two thousand 

 five hundred miles an hour. But the diameter /of Jupiter, and therefore also 

 the circumference, is eleven times greater than that of the earth ; and there- 

 fore, on that account alone, even though he revolved in the same time, the ve- 

 locity of his surface would be eleven times greater than that of the earth. 

 From these two causes combined, it follows that the velocity of the surface of 

 Jupiter at the equator is about twenty-seven and a half times greater than that 

 of the earth, and is, in fact, twenty-seven thousand five hundred miles an hour. 



It is evident, then, that the velocity of the surface of Jupiter produced by his 

 diurnal revolution being nearly twenty-eight times greater than that of the earth, 

 and the sun appearing always vertical to his equator, or nearly so, the causes 

 which produce a system of atmospheric currents parallel to his equator, act 

 with infinitely more energy than upon the earth. We accordingly see the 

 effects of such currents exhibited in the decided arrangements of the strata of 

 his clouds parallel to his equator. Thus we see that there prevail in Jupiter 

 atmospheric currents similar to those which prevail on the earth, blowing 

 constantly from east to west in some latitudes, and from west to east in others. 

 As we cannot doubt that they were intended to fulfil that purpose in the social 

 intercourse of the people of the globe which they actually do fulfill, we are 

 supplied with one analogy more to support the conclusion that the planets are 

 inhabited globes like the earth. 



Annexed are two views of Jupiter, showing the appearance of the belts, 

 taken irom original drawings by Madler, made from observations taken so re- 

 cently as 1841. 



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