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b. A folution of cauftic vegetable alkali alfo 

 renders it immediately turbid, and a white flaky 

 precipitate is depofited. The cauftic vegetable 

 alkali uniting with the vitriolic acid, forms vari- 

 olated tartar, which remains diffolved in the wa- 

 ter, while magnefia being infoluble, is precipi- 

 tated. 



c. But if a folution of mild vegetable alkali, 

 or vegtable alkali combined with fixed air, be 

 made ufe of, there will be no precipitation ; or, if 

 the liquor fhould grow turbid, it will become clear 

 again on being ftirred the magnefia being re- 

 diffolved by means of the fixed air that was con- 

 tained in it. If the liquor be now placed in a 

 warm fituation, and this fixed air be fuffered to 

 efcape, the magnefia will appear in a white pre- 

 cipitate. 



d. By addition of the mineral or volatile al- 

 kalis, in their cauftic and mild ftate, fimilar effects 

 v/ill be produced, as here mentioned, where ve- 

 getable alkali is ufed in its cauftic and mild 

 tafte. 



e. A folution of foap being added to water 

 containing Epfom fait, it becomes turbid, and a 

 number of white flakes are depofited. The al- 

 kali of the foap combines with the vitriolic acid, 

 and formsvitriolated tartar, which remains diffolv- 

 ed in the water, and the unguinous part with the 

 magnefia forming an earthy foap. 



f. A folution of acid of fugar being added, 

 no precipitation will take place, unlefs fome cal- 

 caneus earthy fait be mixed with it, 



B. The nature of the acid contained maybe 

 detected 



g- By 



