1?HYSICAL AND LITERARY, yj^ 



foon becomes rough and difcoloured ; air-!- 

 jDubbles are formed upon it, which foon 

 fly off; and a conftant fucceffion of thefe 

 arife, break, and diffufe themfelves. If a 

 little of this liquor is carefully taken off 

 from the top, even before half the filver 

 is diffolved, and dropt into a muria of 

 fea fait, it will give evident marks that 

 it contains a portion of filver. When all 

 the metal is dilTolved, the folution be- 

 comes clear and limpid, and all is at reft. 

 Thefe things evidently fhew, that fuch me- 

 tallic particles as are freed from their co-? 

 hefion by the faline parts of the men- 

 ftruum recede with them from the fiWer, 

 and are fucceeded by other acid particles 

 to perform their pajt of the operation, un- 

 til all the parts of the folvent are equally 

 jcharged with particles of filver. 



The attradlive force between the fa- 

 line particles of the fpirit of nitre and the 

 filver muft be fuperior to the power by 

 which the particles of filyer attracfl one 

 another; for it difTolves their cohefion, 

 feparatcs them, and keeps them fufpended 

 in a fluid which has only about one tenth 



pari; 



