Fads in Meteorology. 135 



to the same course of the atmospheric currents, and exhibiting the 

 same disastrous effects. In the basin of the south Atlantic we have, 

 on its eastern shore, in South Africa, a barren desert, extending across 

 the same latitudes, and spreading from the shore to the mountains. 

 Over this region prevails a constant southerly wind, being that sec- 

 tion of the great southern circuit which is pursuing its way to the 

 tropics. On the eastern shore of the South Pacific, in the same lati- 

 tudes, we have also the desert of Atacama, and the coast of Peru, with 

 a corresponding section of southerly or circuit wind, a coast which is 

 known to be proverbial for the total absence of rain. 



Additional Observations on Winds. 



Owing to the circuitous character of most winds, the temperature 

 of the wind frequently does not conform to the supposed temperature 

 of the quarter from which it blows. Thus at London, during six 

 weeks of the winter of 1831, a north and north-east wind was accom- 

 panied by a thaw, and a south and south-west wind always by a frost. 

 In Egypt, the south wind is also coldest, in winter. It should be no- 

 ted that the great circuit-winds contain, without the limits of the trades, 

 numberless smaller circuits and eddies of every variety of dimensions, 

 which account for the various and opposite directions and apparent 

 instability of the winds in the higher latitudes. In the United States 

 these irregularities are chiefly confined to the surface winds. 



Near the Canary islands, on the north-west coast of Africa, the 

 trade wind blows from N. N. W. to N. E., the medium direction be- 

 ing N. by E. 



In the most favorable region for the trades, in the Pacific, lat. 12*^ 

 S., Ion. 177° E., the prevailing winds, during near four months in 

 the year, blow strong from W. N. W. 



Many other facts deserve notice in this summary, but the writer 

 does not feel himself at liberty to extend the subject. 



