INTRODUCTION. 



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there are other cIrcnmstanc(>'M which modify or change the climate of particular places. Islands 

 and coasts feel the influence of the sea air, which is not only moist, but is neither very hot nor 

 very cold : it therefore softens the severity of winter, and abates the heat of summer. Conse- 

 quently, places exposed to its influence are rendered more temperate. 



Great accumulations of ice and snow materially affect climate. The great masses of snow 

 and ice in the regions of Greenland impart their chilling influence to the winds, which visit us 

 from the north, and constitute one of the causes of the greater coldness of our climate, than that 

 of other countries in the same latitude. These cold winds, mingled with the sea breezes, 

 which come from the Atlantic, give that harsh and chilling quality so remarkable in the easterly 

 winds of New England. 



Mountains which shelter a country from cold winds, render the chmate warmer. In all 

 parts of our country, the southern dechvities of mountains, and places lying south of them, 

 sheltered from the north winds, are well known to be much warmer. So great is the difference 

 observed in such places, that in some cases plants, which would flourish on the southern side 

 of a mountain, would perish on the northern. 



Elevation above the level of the sea is an important circumstance in climate. The city of 

 Mexico, which according to its latitude should be excessively hot, being elevated 7000 feet 

 above the level of the sea, enjoys a climate of perpetual spring. Quito, which hes under the 

 equator, has a similar climate. Within sight of this city, at an elevation of 15 or 1G,000 feet, 

 the tops of the mountains are so cold as to be covered with never changing masses of snow and 

 ice. At the distance of a few miles, the inhabitants of Guayaquil, living on a low and level 

 margin of the sea, experience an intense and sickly degree of heat. 



Thus we have illustrated, in referring to the climate of America, most of the causes which 

 form or modify climate generally. It may be here added, that man exercises a slow but pow- 

 erful influence upon the climate of those countries, which become the subjects of his labor. 

 By the levelling of forests and the draining of marshes, the sun is let in upon the soil, and the 

 climate is rendered warmer, drier, and more salubrious. Such is the powerful influence of this 

 cause alone, that our own winters are much shorter, the quantity of snow that falls is conside- 

 rably smaller, and the cold far less intense than when our forefathers first settled the country. 

 Some parts of the western country, in the United States, once esteemed exceedingly unheal- 

 thy, since the clearing up of the forests, have become remarkable for salubrity. 



The climate of Europe is affected by various circumstances, rendering some parts more 

 temperate, and others colder or warmer than might be expected from their latitude. The 

 eastern portion of Europe, including two thirds of Russia in Europe, is rendered colder by 

 the winds which sweep over it, chilled by the immense masses of snow and ice embosomed in 

 the mountains of central Asia. The southern parts of Europe are rendered warmer by the 

 hot winds which visit them from the burning deserts and plains of Africa. The extremes 

 both of heat and cold are diminished in those countries which border upon the Atlantic, by the 

 constant action of the sea air. These appear to be the three great causes, which modify the 

 climate of Europe, and render it so different in some parts, from what it is in others of the same 

 latitude ; and so difi'erent from the chmate of those portions of America, which he in the same 

 parallels. 



There is another fact to be taken into consideration, in comparing the climate of the Atlan- 

 tic part of Europe with that of the Atlantic part of North America. In Greenland, and the 

 adjacent regions, there are immense masses of snow and ice, which accumulate from year to 

 year, or are broken up, in the form of icebergs, sometimes reaching the tropics before they 

 are melted. On the contrary, on the borders of Europe, such accumulations do not take place. 

 The gulfs of Norway are almost always open, while the coast of Greenland, exactly oppo- 

 site, is frequently rendered inaccessible, from fixed or floating barriers of ice. 



These considerations will be sufficient to account for most of the contrasts, which we 

 observe between our own chmate, and that of the Atlantic parts of Europe. The climate of 

 England, being surrounded by the sea, is rendered by the sea air much more temperate. The 

 winters in that country are less extreme, than those of the southern parts of New England. New- 

 foundland, although surrounded by the sea, and further south than England, swept by the winds, 

 which come from the icy regions of the north and the adjacent countries, experiences a winter 

 so intense as almost to render it uninhabitable. Spain, Italy, and Turkey in Europe, illustrate 

 the influence of the warm winds of Africa. Situated in the lathude of Massachusetts and New 

 York, they produce oranges, lemons, figs, and grapes, which in our country are the products 



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