WINDS. 



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Trade Winds, with the exception of that towards which the Southeast 

 Trade Wind of the South Atlantic blows. 



Let us take, for instance, the Northeast Trade Wind. 



The heated areas of the land (the Sahara) lie to the east of the 

 Trade Winds. Vast currents of air are passing towards these, almost 

 throughout the year. They come from the north and south as well 

 as the east. On becoming heated over this area, they rise, lose their 

 temperature, and are thence induced towards the nearest warmer area 

 of the ocean lying to the west, on which they descend, some three 

 hundred miles from the Coast of Africa, in about the longitude of 30° 

 west, leaping, as it were, over the currents of air and calms which 

 prevail between it and that coast. They thence pursue their course, 

 rising and descending, to the warm regions of the Gulf of Mexico, are 

 lost in calms, or intercepted by coming in contact with the highland 

 of Mexico, rise again, become cold, and pass to the west, losing their 

 moisture by condensation before reaching the elevated and dry plains 

 of Mexico; thence, leaping the lesser Monsoons of the west coast, 

 they flow towards the warm areas of the Pacific, constituting a part 

 of the Northeast Trade Wind of that ocean. 



The Northeast, as well as the Southeast Trade Winds of the Pacific 

 derive their great supply from the currents of air which rush, in a 

 constant stream, of greater or less velocity, over the vast plains of 

 South America, towards the Andes ; in ascending to escape, they are 

 deprived of their heat and moisture, and are induced towards the 

 heated waters of the Pacific, which they reach, some three to four 

 hundred miles from the coast, in the longitude of 90° to 120°; and 

 thence onwards to the heated areas on the western part of this ocean. 

 The wide belt between these winds and the coast of South America 

 is occupied by the lesser Monsoons of the west coast, over which they 

 have passed. These winds in their onward progress, seek the area 

 which is the nearest and most heated, and tend mostly towards the 

 part of the Pacific which is affected by the direct rays of the sun, at 

 the season. 



As we have stated before, the Northeast Trade Winds are found, on 

 the eastern side of the Atlantic Ocean, to be various in their direc- 

 tions. They are almost entirely different from the western portion ; 

 and this is considered to be a strong argument against the old theory 

 of the Trade Winds, that they do not, where they begin, indicate by 

 their direction the forces that are thought to produce them. In some 

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