210 ON THE GALES OF 



by the accumulation of warm moist air upou the sur- 

 face of the ocean, as those from the north-east are by 

 its accumulation on the Gulf of Mexico. But in the 

 case of the Atlantic, there are no mountains to roll 

 back upon our hemisphere the air displaced by the 

 gales which proceed from it, and to impede the im- 

 pulse thus received, from reaching to the shores of 

 Europe. Our own mountains may procrastinate the 

 flood, and cause it to be more lasting and more ter- 

 rific when it ensues. The course of the wind is na- 

 turally perpendicular to the boundary of the aquatic 

 region producing it, and to the mountainous barrier 

 which delays the crisis. The course of the North 

 American continent is like that of its mountains, from 

 north-east to south-west, and the gales in question 

 are always nearly north-west, or at right angles to 

 the mountains and the coasts. The dryness of our 

 north-west may be ascribed not only to its coming 

 from the frozen zone, where cold deprives the air of 

 moisture, but likewise to the circumstance above 

 suggested, that the air of the ocean is not like that 

 of the Gulf, forced back over our heads to deluge 

 us with rain. 



Other important applications may be made of our 

 chemical knowledge. Thus in the immense capacity 

 of water for heat, especially when vaporized, we 

 see a great magazine of nature provided for mitiga- 

 ting the severity of the winter. To cool this fluid, a 

 much greater quantity of matter must be equally re- 

 frigerated. Aqueous vapour is an incessant vehicle 

 for conveying the caloric of warmer climates to colder 



