106 FARADAY 



and there is a little smoke coming from it. We shall very 

 soon have the vapor rising up. I will make it still hotter, 

 and now we get more of it, so that I can actually pour the 

 vapor out of the flask into that basin, and set it on fire 

 there. This, then, is exactly the same kind of vapor as we 

 have in the middle of the candle ; and that you may be sure 

 .. this is the case, let us try whether 



^ i &) we have not got here, in this 



flask, a real combustible vapor 

 out of the middle of the candle. [Taking the flask 

 into which the tube from the candle proceeded, and 

 introducing a lighted taper.] See how it burns. 

 Now this is the vapor from the middle of the candle, 

 produced by its own heat ; and that is one of the first 

 things you have to consider with respect to the 

 progress of the wax in the course of its combustion, 

 and as regards the changes it undergoes. I will ar- 

 range another tube carefully in the flame, and I 

 FIG. 62 should not wonder if we were able, by a little care, to 

 get that vapor to pass through the tube to the other ex- 

 tremity, where we will light it, and obtain absolutely the 

 flame of the candle at a place distant from it. Now, look at 

 that. Is not that a very pretty experiment? Talk about 

 laying on gas why, we can actually lay on a candle ! And 

 you see from this that there are clearly two different kinds 

 of action one the production of the vapor, and the other 

 the combustion of it both of which take place in particular 

 parts of the candle. 



I shall get no vapor from that part which is already burnt. 

 If I raise the tube (FiG. 61) to the upper part of the flame, 

 so soon as the vapor has been swept out what comes away 

 will be no longer combustible; it is already burned. How 

 burned? Why, burned thus: In the middle of the flame, 

 where the wick is, there is this combustible vapor; on the 

 outside of the flame is the air which we shall find necessary 

 for the burning of the candle; between the two, intense 

 chemical action takes place, whereby the air and the fuel act 

 upon each other, and at the very same time that we obtain 

 light the vapor inside is destroyed. If you examine where 

 the heat of a candle is, you will find it very curiously ar- 



