Meteorology. 333 



ner as fparks can be drawn alternately from an infulated 

 charged jar. I afterwards obferved the fame thing in an- 

 other cat; but, as at that time I paid little attention to this 

 part of philofophy, and fuppofed that the exiftence of the 

 oppofite kinds of electricity in animals might have beca 

 known, I made no farther experiments, and could not de- 

 termine which of thefe eleflricities was negative and which 

 pofitive. I leave it, therefore, to others to examine tliis phe- 

 nomenon with more accuracy." 



METEOROLOGY. 



A very fmgular work was publiflied laft year at Liegnitz 

 in Silefia, entitled Aphorlfms rejpe^t'ing the Infiuence of IVar 

 on the Atmofphere, Weather and Fertility of the Earth. 

 Among the author's obfcrvations are the follovt'ing : If a 

 cubic foot of gun-powder, when it explodes, exercifes a force 

 equal to twenty-nine millions of pounds, it by thefe means 

 produces a great change in the elafticity of the air; the 

 whole mafs of the atmofpkere, within a large circumference, 

 is violently torn, and billow^s of air are produced, which roH 

 themfelves upwards and agitate the vapours contained in 

 them. It cannot therefore be denied that the difcharging of 

 fire-arms and cannon during battles and ficges, and even at 

 great reviews, muft have an influence on the atmofphere, and 

 on the Hate of the clouds and weather. He quotes inftanccs 

 in the time of the feven years war, of clouds and vapours 

 being difperfcd by the explofions of the cannon ; and afltirts 

 that, during his travels through the Tyrol, he faw on feveral 

 occafions, to ufe his own expreffion, the clouds " fhot dead." 

 He obferved in the neighbourhood of Liegnitz, while the 

 tegiment of Wartenlleben were going through their exercife, 

 that the clouds were Ijroken by the explofions, and that the 

 murmuring of the wind, and the agitation of the leaves of 

 the trees, and tl)e fmall feathers fufpended fronj any bodv, 

 were fomelinies ftronger, fometimes weaker, according as the 

 troops fired by battalions or companies. The barometer 

 J rule 



