I 



On Sal Nitrum and Nitro- Aerial Spirit 163 



metals allied to it that sulphur seeks for union ; yet 

 in such wise that the metals, like the alkaline salt, 

 will at once leave it to form a more intimate union 

 with an acid poured upon it. For if an acid liquid 

 such as aqua fortis be poured upon a metal rich in 

 sulphur, say antimony, and then the mixture be 

 heated, the sulphur will be sublimed to a considerable 

 extent, since the acid salt of the liquid uniting with 

 the metal expels its sulphur from its lodgment. 



Lastly, as metals leave their own sulphur that they 

 may combine with an acid salt, so sulphur will quit 

 metals with which it is united, to coalesce in a closer 

 union with a fixed salt. For if a metal abounding in 

 sulphur, such as stibium^ be boiled in strong lye, the 

 metallic sulphur will dissolve in it, since the sulphur 

 seeks to be united with the fixed salt of the lye rather 

 than with the metal ; but this metallic sulphur will be 

 precipitated also from the fixed salt, if an acid salt is 

 poured upon ^t. 



It is also to be noticed here that although sulphur, 

 like an acid salt, can combine with an alkaline salt 

 and with metals, and can be precipitated from them, 

 we must not therefore suppose that a certain acid 

 salt (such as the Oleum Sulphiiris per Catnpanam) 

 lies hidden in a mass of sulphur, and that by its 

 intervention the alkaline salt unites with the sulphur. 

 For if alkaline salt and sulphur united together (as 

 in liver of sulphur) be dissolved in water, and the 

 acid oil of sulphur be then added, the sulphur im- 

 mediately thrust out from its union with the fixed 

 salt will be precipitated. And yet, if the combina- 

 tion of the sulphur with the fixed salt resulted from 

 this, namely, that the acid salt contained in the sulphur 

 unites with the alkaline salt, then the pouring of that 

 acid or oil of sulphur upon them when combined with 



