320 MAGNESIAN EARTH; 



working of the engine. The improvement which I have judr 

 mentioned, of introducing oil into the pipe attached to 

 the fleam veiTel of fuch engines, may alfo be introduced 

 without applying heat externally to the fteam veflfel ; but in 

 this cafe part of the effect which would otherwife be gained 

 is loft." 



v. 



On the Magneftun Earth of Baudijfero. By M. G i o e e r t. 

 (Concluded from Page 284.) 



The earth of JL O afcertain the proportions of thefe conftituent parts of 



Baudiflerp ana- fa Q m agnefian earth, we lixiviated a given weight of it, and 



precipitated the fulphuric acid from one part of it by acetite 



of barytes, and the lime from the other part by oxalate of 



ammonia. 



It contains be- The weight of the oxalate of lime, and that of the fulphate 



fides magnefia, of barytes, obtained from it, fhewed us that it contained 1,60 



fulphate of lime, of ^ fa , phate of jy^ fi " The eX p eriments be f ore recited de- 



— with filex, termine the proportion of the (ilex contained. 



— d b 'c ^° P rove tnat °^ lne carbonic acid, we both calcined a given 



acid, weight of the earth in crucibles, from which fyphons paffed 



into bottles containing lime water; in order that the carbonic 

 acid gas furnimed by the earth might be precipitated, and alfo 

 dlflblved confiderable quantities of it in acids by the aclion of 

 heat, and received the gas produced in bottles filled in like 

 manner with lime water; the rirft method produced conftantly 

 the moil. The carbonate of lime formed in thefe different 

 experiments apprized us that 100 parts of the earth contained 

 from 8 to 1 2 of carbonic acid, and fometimes a little lefs in the 

 fiony fpecies. 



—and water. If this weight of the carbonic acid be deducted from the 



lofs of weight which this earth fuffers by the calcination in the 

 fire, which was mentioned before, we (hall then have the 

 quantity of water which the earth contains. In collecting the 

 relults of the different experiments, it appears that the earth 

 of BaudiflTero is comuofcd of 



MagnefJa 



