7() OK SNOW. 



Formation of after the rtra(um of north wind has either forced a paflage 

 '""**'• through or efFe61ed a union with the fouth-weft wind.* 



Though I have not, in the preceding obfervations, confi- 

 dered the electric fluid as at all efTential to the produdioh of 

 fnow, yet I do not deny theprefence of it. That fnow con- 

 tains the eledric fluid, cannot be doubted; but it does not fol- 

 low, that the latter is nccejfarj/ to the exiftence of the former. 

 We know of no fubftance in nature, that is impervious to that 

 fubtile fluid ; it feems to pervade all bodies with nearly the fame 

 facility as caloric. Therefore, though fnow indicates eleftri- 

 city, it is probably no more than it has acquired in its paflage 

 throligh an ele61rified atmofphere. 



If thofe who are much more competent to (he tafl< than my- 

 felf, would direft their attention to this moft interefting branch 

 of natural philofophy, I am inclined to think, they would find 

 the refult of their enquiries highly gratifying. Meteorology 

 cannot be confidered, but as yet in a ftate of infancy; for the 

 greater part, our knowledge of it is hypothefes, which we 

 cannot fupport by experiment. Therefore, it is only by a clofe 

 obfervation of fatt'^, accompanied by ju ft inferences drawn from 

 them, that we cai> arrive at any degree of certainty on diis 

 complicated fubjedl. 



IV. 



Medico Chemical Ktfenrches oyi the Virtues and Principles of Can- 

 tharides. Bij H. BEAUPOiL.f 



Experiments and -il- HOUGH the animal kingdom prefents us with only a 



obfervations on f,,,^]] number of fubllances of ufe in medicine, it muft never- 

 cantharjdes. . 



thelefs be admitted, that among thofe we poflefs, there are fome 



of which the effed is fo certain, fo conftant, and fo definite, 



that if we were deprived of them, it would be diflicult, and 



perhaps impofllble, to find others to hipply their place. 



Cantharides are of this number; their mode of adtion is uni- 



verfally known, together with the advantages they afford in 



many diforders. It is not, therefore, to be wondered (hat the 



* The water gives out lieat in congehuion. r/^i?Irwlne, Black, 

 Crawford, &c. 

 t Annates deChifnie, XL VIII, 29. 



examination 



