air. We shall see whether it is or not. Put the lighted candle on 

 a piece of blotting paper and a lamp chimney over it, as you see in 

 Fig. 1, and do not forget to give a 

 little air space at the bottom of the 

 chimney. Notice how the partnership 

 continues the same as before. If any- 

 thing, tlie lamp chinmey has made the 

 partnership go on a little faster. Why 

 this is so is a good question for all 

 Junior Naturalists to find out for 

 themselves. Perhaps you will observe 

 some reasons for this if you remove 

 the two lead pencils and place the 

 chimney close to the blotting paper. 

 Watch carefully and see the partner- 

 ship wane, just because the 

 supply of oxygen has been 

 lessened. Next, put a sheet 

 of blotting paper over the 

 top of the chimney, shut off 

 all supply of oxygen and see 

 what will happen. 



The light has gone out. The partnership has ceased because the 

 share that oxygen was required to add could not be supplied. In 

 the bottom of tlie lamp chimney is a compound. It is not oxj'gen 

 or carbon. A little w^iite mouse dropped into this compound would 

 die. It could breathe the compound, but it would do no good, and 

 it would die in the same way that it would if it were plunged into 

 a pail of water. The cause of death in each case might be called 

 drowning. Chemists have named this conq^ound carbon dioxid. 

 The word " di " means two, and has been slipped in between the 

 words carbon and oxygen to denote that oxygen put twice the 

 amount into the compound is did carbon. Do you think you can 

 now explain to your parents how a candle burns? 



All you boys and girls who drank soda water last summer are 



familiar with this compound, carbon dioxid. It sometimes goes tick- 



599 



Fig. 1. 



