28 BOTANY FOR YOUNG PEOPLE. 



the second, a means of getting rid of the 

 carbonic acid which would soon kill us if 

 allowed to remain. Both these objects are 

 answered by the leaves of plants which decom- 

 pose the carbonic acid the moment it touches 

 them. The carbon it retains in its own sub- 

 stance, and sends back the oxygen for the use 

 of animals. You can see from this how depen- 

 dent we are on even the minutest spire of grass 

 or leaf of a moss, and what necessity there 

 was to make the vegetable world a little before 

 the animal. Saadi, the Persion poet, has a 

 beautiful fable on this subject, in which it has 

 been aptly said of him, that he proved as a phi- 

 losopher the harmony in nature which he sung 

 as a poet. Will you read it from this ? 



L. A nightingale is imprisoned in a cage of 

 glass with a rosebush blooming with flowers. 

 Each owes its life to the other. Deprived of 

 fresh air, the bird would soon cease to swell its 

 little throat with harmony. The rose eagerly 

 absorbs the air which has been respired by its 

 loved philomel, and drawing nourishment from 

 it, blushes brighter tints, retaining the carbon, 

 and throwing back the oxygen to be inhaled 

 anew by the bird of song. As often as the 





