MAGNESIAN EARTH. $8$ 



The infufion of the ftony fort afforded differences from the 

 other, with ammonia alfo; this reagent did not ever trouble 

 the infufion of the friable fpecies, but always troubled, though 

 /lightly, the infufion of the ftony variety. 



It follows from thefe obfervations that, befides the fulphate 

 of lime which both kinds of the earth of Baudiffero contained, 

 the ftony variety held in union muriatic acid, perhaps in com- 

 bination, partly with the lime, which there was not furficient 

 fulphuric acid to faturate, and partly united to another earth, 

 which was not lime, fince its folulion permitted itfelf to be 

 decompofed by ammonia; and it will appear that this earth 

 ^ was magnefia. 



The fulphuric, nitric, and muriatic acids attack this earth, The ancient mU 

 when it is well divided into an extremely fine powder. "Yk ^ $ n ^ t { y9 



Their action however is but little apparent, but on the leaft earth, 

 addition of heat it becomes ftrongly marked. Very fmall bub- 

 bles of gas, which rife from the bottom of the liquor, a flight 

 white fcurh which forms itfelf at the furface, and a fmall hiflZ. 

 jng, (hews plainly that there is a difengagement of an aeri, 

 form fluid or effervefcence. 



When the earth has been previoufly calcined in the fire, With great f$xe 



their action is very different. There is not, as may be fore- % P<y eviov »% 

 r rr r ■ ■, t . calcined. 



feen, any effervelcence ; but the mixture grows hot, to that 



degree that a true ebullition enfues; in fome minutes the mix- 

 ture aflumes a folid form, caufed by a kind of jelly produced 

 for it. 



The acid which has the greateft aclion on it is the muriatic The muriatic 

 acid, and after this the nitric, and the fulphuric acid after both, ^dacls-more 

 This laft however does not diflblve without much difficulty the 

 whole of the foluble part, and that after a long continued 

 ebullition. 



. The folution made in the clofed veffels difpofed fo as that the 

 gas may be received, forms with lime-water carbonate ©f lime, 

 which confirms the difengagement of a little carbonic acid be-, 

 tore indicated by the calcination of this earth in the fire. 



The folutions of this earth in the acids are perfectly colour- 

 lefs. 



The prufliate of lime or the oxalate of ammonia do not at 

 all trouble them. 



Ammonia forms with them an abundant precipitate. Ammonia pre- 



Th*» cipitatea the fo* 

 1 " c lution as does 

 likewife the car- 

 bonate otpotaih. 



