528 THUNDER-STORMS. 



of the flashes from the same cloud, which often follow each other in rapid sue- 

 cession, contrary to what takes place in metallic conductors in which the elec- 

 trie equilibrium is restored in a single discharge, or nearly so. The most ob- 

 vious way of explaining this is by supposing that the vapor composing thunder 

 clouds being a much less perfect conductor than metal, and the cloud being 

 often of extensive magnitude, possibly measuring miles in length or breadth, 

 the equilibrium cannot be restored, except by successive discharges, accord- j 

 ing as the fluid dispersed over or through the cloud can collect at or near the ) 

 striking point. 



