372 Elements of Mineralogy. 



leaft, that by diminifhing the proportion of 

 iron, the fpecific properties of the compound 

 would be altered, which is not true with re- 

 fpedt to thefe femi-metals, for the freer they 

 are from iron, the more perfectly they ma* 

 nifeft their peculiar properties ; fo that in 

 every fenfe this afiertion is either falfe or un- 

 intelligible. 



With refpeft to zinc and cobalt, there is 

 not the leaft foundation for fufpe&ing, much 

 lefs affirming, their exiftence in regulus of 

 manganefe, as they are never found even in 

 the ore of manganefe, except fortuitoufly ; 

 but, on the contrary, this ore is moft fre- 

 quently found without a particle of either ; 

 nor does the regulus fhew any property that 

 approximates it more to them than to other 

 metallic fubftances, but, on the contrary, 

 many that belong to no other, nor to any 

 compound of any other metallic fubftances. 



APPENDIX 



