y8 STUDIES OF NATURE. 



of the Currents, which fweep them along toward 

 the Line, they advance fometimes as far as to the 

 45th degree, cooling the Seas of the South, by 

 their vaft efFufions. Thus the ices of the Pole 

 communicate coolnefs to the heated feas of Africa, 

 juft as the burning fands of Africa tranfmit warm 

 winds to diffolve the ices of the Pole. 



But as cold is, in it's turn, a very great bleiling 

 in the Torrid Zone, Nature employs a thoufand 

 methods to extend the influence of it in that Zone, 

 and to mitigate in it the heat and the light of the 

 Sun. Firft, Ihe deftroys there the refractions of the 

 Atmofphere. There is fcarcely any twilight between 

 the Tropics, to precede the rifing of the Sun, and 

 flill lefs after his fetting. When he is in the Ze- 

 nith, he veils himfelf with rainy clouds, which 

 cool the ground, both by their made and by 

 their mowers. Befides, thofe clouds being fre- 

 quently impregnated with thunder, the explofion 

 of their fires dilates the fuperior ftratum of the 

 Atmofphere, which is icy at the height of two 

 thoufand five hundred fathom, under the Line, 

 as is evident from the fnows which perpetually co- 

 ver, at that height, the fummits of fome of the 

 Cordelier mountains. They caufe to flow down, 

 by their explorions and concuffions, columns of 

 that air, congealed in the fuperior regions of the 

 Atmofphere, into the inferior, which are fuddenly 



cooled 



