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the day, from 17 to 2 lines on the electrometer 

 of Volta, becomes extremely variable from the 

 month of March. It appears null during whole 

 days ; and then for some hours the pith balls of 

 the electrometer of Volta diverge three or four 

 lines. The atmosphere, which is generally in 

 the torrid, as well as in the temperate zone, in a 

 state of vitreous electricity, passes alternately, 

 for eight or ten minutes, to the resinous state. 

 The season of rains is that of storms ; and yet a 

 great number of experiments, made during three 

 years, prove to me, that it is precisely in this 

 season of storms we find the electric tension 

 least in the lower regions of the atmosphere. 

 Are storms the effect of this unequal charge of 

 the different superincumbent strata of air ? What 

 prevents the electricity from descending toward 

 the earth, in an air become more humid since 

 the month of March ? The electricity at this 

 period, instead of being diffused throughout the 

 whole atmosphere, appears accumulated on the 

 exterior envelope, at the surface of the clouds. 

 According to Mr* Gay-Lussac it is the formation 

 of the cloud itself, that carries the fluid toward 

 it's surface. The storm rises in the plains two 

 hours after the Sun has passed the meridian ; 

 consequently a short time after the moment of 

 the maximum of diurnal heat under the tropics. 

 It is extremely rare in the islands to hear thun- 



