EFFECTS OF CHEMICAL AFFINITY. 91 



derson will put a candle under that jar, and you 

 will see how soon the water is produced (fig. 30). 

 Look at that dimness on the sides of the glass, 

 which will soon produce drops, and trickle 

 down into the plate. Well, that dimness and 

 these drops are water, formed by the union of 

 the oxygen of the air with the hydrogen exist- 

 ing in the wax of which that candle is formed. 

 And now, having brought you in the first 

 place to the consideration of chemical attrac- 

 tion, I must enlarge your ideas so as to include 

 all substances which have this attraction for 

 each other for it changes the character of 

 bodies^ and alters them in this way and that 

 way, in the most extraordinary manner; and 

 produces other phenomena wonderful to think 

 about. Here is some chlorate of potash, and 

 there some sulphuret of antimony. ( 17 ) We will 

 mix these two different sets of particles together, 

 and I want to show you in a general sort of 

 way, some of the phenomena which take place 

 when we make different particles act together. 

 Now I can make these bodies act upon each 

 other in several ways. In this case I am going 

 to apply heat to the mixture, but if I were to 

 give a blow with a hammer the same result 



