THE \\EATHER, AND WEATHER PROPHE1S. 165 



Now this cause of reinforcement cannot begin to be felt 

 until the sun, having passed the equinoctial, has ad- 

 vanced considerably towards the other solstice. In the 

 case of the northern anti-trade, the effect in question is 

 rendered still more sensible by the great preponderance 

 of sea in the southern hemisphere as compared with the 

 northern ; and the much greater quantity of vapour 

 raised by the summer sun on that side of the equator. 

 And besides all this, it will be remembered that all the 

 air which had been dragged across the equator into the 

 southern hemisphere by transferred vapour during the 

 continuance of our northern summer, and there as it 

 were imprisoned, is now released ; and returns, neces- 

 sarily by the same course, and contributes to reinforce 

 the northern anti-trades. 



(29.) There is a special cause, too, arising from the 

 geographical position of Britain and north-west Europe, 

 in relation to the South American continent, which is 

 probably not uninfluential in producing or aggravating 

 this disturbance. If we trace on a map the course of 

 the wind which reaches our island from the south-west, 

 we shall find that it has its origin on the coast of Guiana, 

 between the fiftieth and sixtieth degrees of west longi- 

 tude. This also is nearly about the point where the 

 medial line between the north and south trades, in its 

 average position, intersects the South American coast. 

 Here the South American continent is comparatively 

 narrow, but south of this it expands in longitude, and 

 between the fifth and fifteenth degrees of south latitude 

 has an average breadth of between 30 and 40. 



