KEMARKS, 5CG. 



crful between the tropics than elsewhere. Hence, 

 if the earth was an even and solid plain, it is proba- 

 ble, that there would be a regular circulation in both 

 hemispheres, of heated and rarefied air, in the upper 

 parts of the atmosphere, from the equator toward 

 the polar regions ; and from these, in return, an 

 equal supply of refrigerated and condensed air, is 

 attracted over the earth's surface, toward the zone» 

 where the sun is vertical. If there was no collate- 

 ral or counteracting force, the columns of cold and 

 heavy air, from the poles, would move towards the 

 equator in lines as straight as meridians. The di- 

 rections in which such a chilled and ponderous ail? 

 ought to move, would be south. But there is a colla- 

 teral or counteracting force. This is the Atlantic 

 ocean, which stretches from one end of the conti- 

 nent to the other. The mean temperature of this 

 immense body of waters, may be estimated, at least, 

 as high as 60 deg. of Fahrenheit; while the mean 

 temperature of the snow and ice, lying far inland, 

 may be estimated as very far below the freezing 

 point of water, and often in high latitudes as low 

 as 0, or lower. Here then is a great disparity be- 

 tween the heat of the Atlantic ocean, and that of the 

 gi-eat continent, lying to the west of it; and stretch* 

 ing an immeasurable extent in that direction. A 

 consequence of this must be, th^t the refrigerated 

 and condensed air, of the interior and mountainous 

 country, will be attracted, over the earth's surface, 

 toward the warmer spaces, occupied by the ocean. 

 If there was no counteracting force, the columns o£ 

 Cekl and heavy air, from the mountain's antjl gdi^ 



