REGION OP THE "TRADES." 221 



pushes out two or three degrees in summer, and 

 in winter retreats a little within the latitudes I 

 have mentioned. Accordingly, the summer limit 

 of the north-east trade-wind lies somewhat to the 

 north of the Canary Isles, and in America em- 

 braces the states of Florida and Georgia. 



The south-east trade-wdnd prevails between 3° 

 north latitude and 25° south latitude, with, how- 

 ever, certain changes due to the position of the sun. 

 And the belt of the calms lying between the north- 

 east and south-east trade-wind, and having a 

 breadth of five or six degrees of latitude, does not 

 always remain in exactly the same place, but in 

 summer advances towards the north, and retreats 

 in winter ; always, however, in the Atlantic Ocean, 

 keeping to the north of the equator. 



The trade-winds set out from the middle of 

 Africa, and extend, probably in consequence of 

 the great masses of land and the hot sand-deserts 

 of Northern Africa, as well as by reason of the 

 warm waters of the Atlantic equatorial current, 

 farther on the north than on the south side of the 

 equator. Over the continent of South America 

 they may be traced as far as the chain of the 

 Andes. 



The trade-winds of the great ocean are first 

 felt at a considerable distance from the American 

 coasts, from which they blow regularly the whole 

 year round, on the north of the equator to the 



