386 AN AURORA BOREALIS, &C. 



electricity when hot as when cold. The fact 

 which I discovered on Clapham Common, near 

 London, is still more in point :* for although it 

 be the reverse of that we are looking for as 

 directly in corroboration of the supposition, 

 we can easily understand that if electricity will 

 drive heat before it, (into a corner as it were,) a 

 prevailing intensity of heat will drive electricity 

 from one part of a body to another part of it. 

 Indeed, all our thermo-electric experiments are 

 demonstrative of the fact. 



Under this supposition then, the earth would 

 continually be electro-polar ; being negative 

 where the sun's heat is most intense, with respect 

 to the colder regions ; where, in consequence of 

 its redundancy, the fluid might spring up into 

 the air, by the help of aqueous vapour, &c. and 

 thus produce the Aurora : the northern when the 

 sun is on the southern hemisphere, and the south- 

 ern when he is on the northern hemisphere. This 

 of course, is a mere opinion that I have formed out 

 of the materials described in this paper. 



* The fact here alluded to was developed by means of an 

 extensive Voltaic battery, and showed that an electric current 

 is capable of producing an intense heat by its repellent action 

 on the calorific matter. 



