Air 



207 



allowing a few drops of the melted wax to drop on 

 the block, and then holding the bottom of the candle 

 on this melted wax until it begins to solidify. Over 

 the candle place a tall glass lamp-chimney (see Fig. 

 61) so that the bottom of the chimney rests on the 

 block and the candle is in the centre of the chimney. 

 Watch the candle flame. It will be observed that it 

 flickers and becomes smaller and smaller. If the 



Fig. 61. 



Fig. 62. 



chimney be sufficiently tall and narrow, the candle 

 at length goes out. 



Relight it and replace the chimney, this time 

 supporting the base of the chimney on two strips of 

 wood (Fig. 62) so that there is an air-space between 

 the base and the wooden block. Again note carefully 

 the behaviour of the candle flame. It now burns 



