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glass. Six pounds of mercury being exposed to the air 

 in a china-plate, the dew ran in streams on the edge of 

 the plate, but not a drop was on the mercury. 



Is there not some alliance between the phenomena 

 observed in dew, and those which appear in electric 

 bodies? All hard bodies may by rubbing become elec- 

 tric, excepting only metals. .And metals are the only 

 bodies which wholly refuse to admit dew. 



But this is not all ; a pewter plate placed all night in 

 the open air, receives no dew on its upper side, but the 

 under side is covered with it. On the contrary, place a 

 china plate near it, and the upper side of it is quite wet, 

 but the under side is quite dry. So one receives the 

 dew only on the upper, the other only on the under sur- 

 face ! Who can account for this ? 



Mr. Kershaw has observed, that dew newly gathered 

 and strained, is not very clear, but of a yellowish colour. 



That when he endeavoured to putrefy it by various 

 degrees of heat, he quite failed of his intention : for heat 

 rather clarified and preserved it sweet, than caused any 

 putrefaction : 



That after it had been exposed to the sun, corked up, 

 for a whole summer, there was no other change than 

 that much green stuff (such as we see in standing water) 

 floated on the top : 



That after it had been exposed to the sun many 

 weeks in an open glass, it was full of little insects like 

 tadpoles, which in a while dropt their skins, and became 

 gnats ; 



That vapouring away great quantities of this dew, he 

 procured two pounds of greyish earth which lay in 

 leaves one ;.bove another, like brown paper, but very 

 friable : 



Lastly, that by often calcining and filtering this earth, 

 he extracted two ounces of fine, small, white salt, which 

 much resembledrock salt, when it was viewed through 

 a microscope: 



If clouds arc condensed, so as to fall in drops, this we 



