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they are negatively electrified, although the effects and 

 appearances are nearly the same, yet the manner of 

 operation is different. For in this case, it is really the 

 fire from the mountains, or other parts of the earth, 

 which strikes into the cloud : and not as we imagine, 

 fire from the cloud which strikes into the earth. And 

 we may easily conceive how a cloud may be negatively 

 electrified. When a portion of water is rarefied into a 

 thin vapour, the fire it contains is rarefied too. Con- 

 sequently it has then less than its natural quantity of 

 fire. Such a cloud therefore coming within a due 

 distance of the earth, will receive from it a flash of 

 electric fire; which flash, to supply a great extent of 

 cloud, must often contain a great quantity of fire. 

 Such a cloud aiso pacing over woods of tall trees, may 

 silently receive some ^app;y either from the points of 

 the boughs, or from the sharpest ends and edges of the 

 leaves. The cloud thus supplied, flashes into other 

 clouds that have not been so supplied ; and those into 

 others, till an equilibrium is produced, among all that 

 are within a striking distance of each other. And hence 

 are repeated strokes and flashes, till - they descend iu 

 showers to the earth, their original. Rain, especially 

 when in large drops, generally brings down the electric 

 fire: falling snow, often: summer hail, always, though 

 silently. Consequently any of these may prevent thunder 

 and lightning; or, at least abate its violence. Rain is 

 helpful in another respect likewise. By wetting men or 

 beasts, it saves many lives. For if your clothes are 

 thoroughly wet, and a flash of lightning strikes the top 

 of your head, it will run in the water over the surface 

 of your body in the ground : whereas if your clothes 

 were not wet, it would go through your body. Hence 

 a wet chicken cannot be killed by a stroke from the 

 phial :. whereas a dry one is killed in an instant. See here 

 also the wisdom and goodness of Him, who sendefh 

 forth lightning with the rain ! It should likewise 

 be observed, that wherever electrified clouds pass spires, 

 towers, chimnies, and high trees, as so many points draw 

 the electric fire, and the whole cloud frequently dis- 



