64 STUDIES OF NATURE. 



parched and dry fituations, as chains and rods of 

 iron attract thunder-clouds. It is true, that 

 Princes mud be at the expenfe of fuch coflly and 

 ^ufeful experiments ; but it is the way for them to 

 immortalize their memory. The Pharoahs, who 

 built the pyramids of Egypt, would not have 

 drawn upon themfelves the curfes of theiF fubjects, 

 as Pliny allures us they did, for their enormous 

 and ufelefs labours, had they reared, amidffc the 

 fands of Upper Egypt, an electrical pyramid, 

 which might there have formed an artificial foun- 

 tain. The Arab who (hould refort thither, at 

 this day. to quench his thirft, would ftill pro- 

 nounce benedictions on names which, if we may 

 believe the great Natural Hiftorian, had already 

 funk into oblivion, and ceafed to be mentioned, 

 in his time. 



For my own part, I think that feveral metals 

 might be proper for producing fimilar effects. An 

 officer of high rank, in the fervice of the King of 

 Pruffia, informed me that, having remarked va- 

 pors to be attracted by lead, he had employed it's 

 attraction for drying the atmofphere of a powder- 

 magazine. This magazine was conftructed under 

 ground, in the throat of a baftion, but had been 

 rendered of no ufe whatever, from it's humidity. 

 He ordered to line with a coat of lead the con- 

 cave ceiling of the arch, which was before planked 



over, 



