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tial Ocean, and which is the effect of the polar 

 currents, produce, under the tropics, a sensible 

 diminution of the temperature of the earth ? 

 Is this temperature below that of the atmos- 

 phere? This we mean to examine hereafter, 

 when we have collected more facts in the high 

 regions of the Cordillera of the Andes. 



