fio* OF THE ASBESTINE EARTH. 



befli, the Tarentaifian approaches fo near to the 

 genuine, that it is a quetlion whether it fliould be 

 feparated from it. It lias the fame principles, 

 arranged in the fame order, with the addition of 

 vitriolated terra ponderofa only, and which does 

 not fcem to have been combined by the hazard 

 of neighbouring iltuation, but by a more inti- 

 mate and perfect union with all the parts, as it 

 efcapes the penetration even of aifiiled viilon. 

 The albedos of Taremaife, then, conftitutes the 

 ninth fpccies of the Magnefian genus; to which 

 perhaps the inilgnificant name of amianthus a p. 

 plies, thai would orherwife be fuperfluous. But 

 ive will now attend to a fpecific difference. 



The amianthus compoftrd of llliceous, mag- 

 neiian, and calcareous earth, terra ponderolu, 

 vitrioldta, argillaceous earth, and a portion of 

 iron. Whoever has had an opportunity of exa- 

 mining this fubflance in large quantities, on the 

 fpol where it is found, fliouUl have iuvciligated 

 whether the mixture of the terra ponderola is 

 merely mechanical. For were it no otherwise 

 united, it would fcurcely remit fo much the ac- 

 tion of acid menflrua, a> we ilud b> experience 

 that it does. The progreOion from the ilcatites, 

 through the lleatiibrm ufbeltos, to the foftcft 

 variety of albedos, defcribcd under the third 

 and fifth heads, is ibmething remarkable. 

 The firfl diilers folely by its wanting the cal- 

 careous earth ; which feems in fome meafure 

 lo imply a conlideiablc power in this tfarth to 



form 



