EQUATORIAL BAINS. 149 



We have nere considered the cessation of the breezes as 

 khe principal cause of the equatorial rains. These rains in 

 each hemisphere last only as long as the sun has its decli- 

 nation in that hemisphere. It is necessary to observe, that 

 the absence of the breeze is not always succeeded by a dead 

 calm ; but that the calm is often interrupted, particularly 

 along the western coast of America, by bendavalrs, or south- 

 west and south-east winds. This phenomenon seems to 

 demonstrate that the columns of humid air which rise in the 

 northern equatorial zone, sometimes flow off toward the 

 south pole. In fact, the countries situated in the torrid 

 zone, both north and south of the equator, furnish, during 

 their summer, while the sun is passing through their zenith, 

 the maximum of difference of temperature with the air of the 

 opposite pole. The southern temperate zone has its winter, 

 while it rains on the north of the equator; and while a mean 

 heat prevails from 5 to 6 greater than in the time of 

 drought, when the sun is lower.* The continuation of the 

 rains, while the bendavales blow, proves that the currents 

 from the remoter pole do not act in the northern equi- 

 noctial zone like the currents of the nearer pole, on account 

 of the greater humidity of the southern polar current. The 

 air, wafted by this current, comes from a hemisphere consist- 

 ing almost entirely of water. It traverses all the southern 

 equatorial zone to reach the parallel of 8 north latitude ; 

 and is consequently less dry, less cold, less adapted to act as 

 a counter-current to renew the equinoctial air and prevent 

 its saturation, than the northern polar current, or the breeze 

 from the north-east.f We may suppose that the bendavales 

 are impetuous winds which, on some coasts, for instance on 

 that ol Gruatimala, (because they are not the effect of a 

 regular and progressive descent of the air of the tropics 

 towards the south pole, but they alternate with calms), are 

 accompanied by electrical explosions, and are in fact squalls, 



* From the equator to 10* of north lat. the mean temperatures of the 

 summer and winter months scarcely differ 2 or 3 ; but at the limits of 

 the torrid zone, toward the tropic of Cancer, the difference amounts 

 to 8 or 9. 



t In the two temperate zones the air loses its transparency every time 

 that the wind blows from the opposite pole, that is to say, from the pole 

 that has not the same denomination as the hemisphere in which the wind 

 blows. 



