152 Chemistry. [Lecture 20. 



tough substance is the result of this mixture. 

 Two ounces of each of these ingredients, shaken 

 together in a corked phial, became instantly 

 hot, and being set down, forced the cork, and 

 every drop passed out with a hissing noise, 

 forming a very thick dark cloud, from which fell 

 a strong, acid, bituminous ram all over the room. 

 This experiment, it must be remarked, cannot 

 be repeated without some degree of danger. 



Uncombined with oxygen, you have seen, sul- 

 phur wants the acid properties fit is quite mild 

 and harmless, and proves a safe and salutary 

 medicine. The acid attracts water violently; 

 but sulphur is incapable of being combined with 

 water, unless we have something that has a great 

 attraction for water to it : the activity of it there- 

 fore wholly depends on its combination with 

 oxygen. This is indeed the case with all those 

 radical substances which are the bases of the 

 acids. Sulphur, however, possesses some of the 

 properties of the acids, though in a low degree. 

 It has an attraction for alkalies ; for by mixing 

 potass and sulphur, both in powder, and pour- 

 ing boiling water upon them, they act upon 

 each other, and the sulphur is rendered so- 

 luble in water. The mixture always turns the 

 water to a deep colour, yellow, green, or a deep 

 red (the solution of the alkali alone would have 

 been colourless), and it has the smell of rotten 

 eggs, or the scouring of a gun, which scouring 

 of a gun is produced from a sulphuret of potass. 



