CHEMICAL HISTORY OF A CANDLE 



115 



combustion on a little larger scale. From that candle 

 ascends heated air, and two or three experiments will show 

 you the ascending current ; but, in order to give you a notion 

 of the quantity of matter which ascends in this way, I will 

 make an experiment by which I shall try to imprison some 

 of the products of this combustion. For this purpose 1 have 

 here what boys call a fire-balloon; I use this fire-balloon 

 merely as a sort of measure of the re- 

 sult of the combustion we are con- 

 sidering; and I am about to make a 

 flame in such an easy and simple 

 manner as shall best serve my present 

 purpose. This plate shall be the 

 "cup," we will so say, of the candle; 

 this spirit shall be our fuel ; and I am 

 about to place this chimney over it, 

 because it is better for me to do so 

 than to let things proceed at random. 

 Mr. Anderson will now light the 

 fuel, and here at the top we shall get 

 the results of the combustion. What 

 we get at the top of that tube is ex- 

 actly the same, generally speaking, as 

 you get from the combustion of a 

 candle; but we do not get a luminous 

 flame here, because we use a sub- 

 stance which is feeble in carbon. I 

 am about to put this balloon not 

 into action, because that is not my 

 object but to show you the effect which results from the 

 action of those products which arise from the candle, as they 

 arise here from the furnace. [The balloon was held over 

 the chimney, when it immediately commenced to fill.] You 

 see how it is disposed to ascend; but we must not let it up; 

 because it might come in contact with those upper gaslights, 

 and that would be very inconvenient. [The upper gas- 

 lights were turned out at the request of -the lecturer, and 

 the balloon was allowed to ascend.] Does not that show 

 you what a large bulk of matter is being evolved? Now 

 there is going through this tube [placing a large glass tube 



FIG. 64 



