ON ATMOSPHERIC PHENOMENA. 



109 



opposite zones, in the same manner as it charges semicon- 

 ductors, and as their natural fluid is distributed in the state 

 of charge in nonconductors; and the gasses of water, not- The principles 

 withstanding the lightness of one of them, dissolve in the °^uTtn*"i*. 

 air as spirit of wine dissolves in water, and remain diifused 

 in the matter of the cloud. Soon, by the condensation of Discharge of 

 the fluid, or the intensity of the charge, this state destroys tile clouds - 

 itself; the fluid bursts from stratum to stratum, and the 

 water is recomposed by the inflammation of its gasses. 

 The fulguration or flashes of lightning without or almost Lightning of 

 without noise, and the light of which perfectly resembles tw0 kind*. 

 that of the electric spark, are the effects of the explo- 

 sion'of the fluid of that spark; and the flashes accompa- 

 nied with thunder, or true lightning, which diffuse the 

 same light as the combustion of hidrogen and oxigen gas, 

 are those of the combustion of the gasses of water. These 

 two sorts of lightning alternate with each other, because 

 the decomposition and recom position of water take place 

 alternately. The rolling of thunder arises from a succession Thunder 

 of partial inflammations, in proportion as the strata oppo- 

 sitely electrified confound their two states. The sounds too f twokiaft?, 

 are different ; that of the figurations being acute, quick, 

 snapping; and that of the fulminations heavy, dull, rolling; 

 and, from their analogy to the sounds produced by electric 

 sparks and the combustion of hidrogen and oxigen gas in 

 our experiments, may easily be referred to the phenomena, 

 to which they belong. 



The sound of the combustion is more intense, because a Cause of the 

 vacuum is formed, which is instantly filled, and more than intensity of the 

 filled, by the vapour of water, that acquires a state of con- 

 siderable expansion. When once the rain has begun to fall 5 Progress of th£ » 

 and the work of the storm is set a going, it proceeds of it- sloim * 

 self, or has no longer occasion for the formation of fresh 

 clouds to keep it up ; the caloric that separates from the 

 combined gasses transforming itself into electricity, which 

 in its turn decomposes a portion of water; so that the work 

 of the successive decompositions and compositions continues 

 by the effect of it's alterations, and is kept up of itself, till 

 all the water diffused through the surrounding air by vapo- 

 rization is condensed there, and resolved into rain; or till, 



by 



