716 LECTURE LVII. 



The phenomena of waterspouts, if not of electrical origin, appear to have 

 some connexion with electrical causes. A waterspout generally consists of laro-e 

 drops, like a dense rain, much agitated, and descending or ascending with a 

 spiral motion, at the same time that the whole spout is carried along horizon- 

 tally, accompanied in general hy a sound like that of the dashing of waves. 

 Spouts are sometimes, although rarely, ohserved on shore, but generally in 

 the neighbourhood of water. They are commonly largest above ; sometimes 

 two cones project, the one from a cloud, the other from the sea below it, to meet 

 each other, the junction being accompanied by a flash of lightning: and 

 when the whole spout has exhibited a luminous appearance, it has perhaps 

 served to conduct electricity slowly from the clouds to the earth. Some of 

 these circumstances may be explained by considering the spout as a whirlwind* 

 carrying up drops of water, which it has separated from the surface of the 

 waves; and the remainder may perhaps be deduced from the cooperation of 

 electricity, already existing in a neighbouring cloud. 



It is doubtful whether the light of the aurora borealis may not be of an elec- 

 trical nature: the phenomenon is certainly connected with the general cause 

 pf magnetisrn ; the primitive beams of light are supposed to be at an eleva- 

 tion of at least 50 or 100 miles above the earth, and every where in a direc- 

 tion parallel to that of the dipping needle ; but perhaps, although the sub- 

 stance is magnetical, the illumination, which renders it visible, may still be 

 derived from the passage of electricity, at too great a distance to be dis- 

 covered by any other test. 



Earthquakes and volcanos appear to originate in chemical changes, which 

 take place within the substance of the earth: they have probably little 

 further connexion with electricity, than as causes which occasionally destroy 

 the electrical equilibrium ; for although some authors have inferred, from the 

 great velocity with which the shock of an earthquake is transmitted from 

 place to place, that its nature must be electrical, yet others have, with 

 greater probability, attributed the rapid, succession of the effects to the 

 operation of a single cause, acting at a great distance below the earth's sur- 

 face. There are however some circumstances, which indicate such a con- 

 nexion between the state of the atmosphere and the approach of an earthquake, 

 as cannot easily be explained by any hypothesis. 



