94? Chemistry. [Lecture 27. 



vitriol) consists of heavy inert particles, which 

 contain a quantity of fire, and that upon appli- 

 cation of the water the particles are dissolved, 

 and the particles of fire break loose and become 

 active ; but these reasoners would be puzzled to 

 explain the phaenomenon of the same sulphuric 

 acid, or oil of vitriol, with ice. In explaining 

 the dissolution of marble, they say, the acid 

 contains innumerable wedges or needles, which 

 get into the pores of the marble, and throw off 

 its particles, which are suspended in the fluid 

 like a boat by its oars*. But supposing the par- 

 ticles sharp and pointed, they would require a 

 force to make them act. In answer to this, they 

 tell you that the particles of fluids are agitated 

 in a constant and irregular manner ; they refer 

 you to the beams of the sun let into a chamber, 

 in which you will see the particles of dust, mov- 

 ing in all directions. It is true, there is a mo- 

 tion of this kind in the air, which is the most 

 elastic and tremulous of all fluids, every motion 

 throwing it into agitation; but this is not so 

 rapid as to throw the particles against each other 

 with sufficient force to produce the effects in 

 question. There are many instances of solid 

 bodies acting with violence upon one another, 

 as corrosive muriate of mercury, when powdered, 

 and mixed with pure antimony in powder. 

 There are many facts also relating to fluids, 



* This is the very expression of Lemery. 



