276 Of the Vitriol 



at the fame time, and that, occafionally, in quite 

 different proportions •, but iron-vitriol and copper- 

 vitriol, do not agree in one and the fame yield of 

 metal : and 'tis well known, that cryftalline falts, 

 when paffing through fudden evaporations, and 

 quick cryftallifations, are always more watry than 

 others, worked (lower, and more leifurely •, and 

 thefe laft, as being clofer, more faturated, and 

 rich in colour, are prepared by dyers, and the like 

 fort of people, efpecially if coppery. 



The form or nature of the vitriolic texture and 

 cohefion, is perfectly faline, and therefore vitriol 

 is juftly called a falt^ and, to diftinguifh it, a 

 metallic fait -, for, when pure and frefh, it appears 

 tranfparentj moreover, it is on the tongue a 

 faline, fharp tafte; laftly, it is not only the 

 being perfectly diffoluble in common water, fo as 

 the water fhail remain clear and transparent (unlefs 

 the air and warmth happen to dry it up, when 

 fuch a folution is apt to let fall fomething undif- 

 iolved, and the water to remain a fmall time tur- 

 bid) but it alfo pafTes with the water, in its entire 

 mixtion, quite through the clofeft {trainers. 



Yet, under the title of a metallic fait, we arc 

 not here to include a fort, parable, or rather fe- 

 parable from metals themfelves, without the ad- 

 dition of any thing foreign, and confequently with- 

 out the fulphur-acid, a distinction fully made out 

 by Dr. Rothe, in his differtation on metallic falts ; 

 neither are we to judge of it by the flandard or 

 fcale of acid and aicali, as in the artificial exhibi- 

 tion of vitriol from its acid fait and iron, there 

 ufually happens an effervefcence and incalefcence 

 by means of thefe two parts : nor can we admit, 

 that becaufe alcali's effervefce with acids, all bo- 



dic5 



