CHAP. 7. 3. OF ELECTRICITY: 217 



appear without clouds were only at too great a 

 distance for the clouds from which the flashes 

 come to be seen. In either case the communi-* 

 cation may often be with the ground, which, 

 in the damp of the evening, with falling dew, 

 woulpl not be violent, as the general moisture 

 would afford a more free and latent, and, 

 consequently, a more gentle passage to or from 

 the Earth.* Upon this principle, we may see 

 also why nocturnal Storms are generally less 

 mischievous than those which happen in the 

 day time, and why there is additional security 

 in Thunderstorms after the Rain has begun to 

 falLf 



* The Abbe Bertholon thought he could determine when 

 the Lightning rose from the ground to the cloud, and when it 

 descended from the cloud to the ground. Bertholon, Elec. 

 Met. vol. i. c. iv. p. 132. He refers to a letter of Maffei, 

 Delia Formazione del Fulmine, in the Journal de Venice. 

 Tom. xxxii. art. 7- 



t This ought to suggest the propriety of keeping the 

 ground about the place of insertion of the Metalic Conductors, 

 or Lightningtraps, as they are called, moistened with water, to 

 effect a freer entrance of the fluid. The Pointed Conductors 

 are the most useful. 



