The Story-Book of the Fields 



seen that this gas, the chief food of the plant, 

 is made up of carbon combined with oxygen 

 —that component of the air which is fit for 

 breathing. Under the influence of the sun- 

 light the leaves decompose this gas ; the 

 oxygen is set free, becoming fit for the breath 

 of animals and for combustion, while the 

 carbon remains in the plant, and in conjunc- 

 tion with the materials supplied by the rising 

 sap, becomes the nourishing fluid, the de- 

 scending sap, from which the whole substance 

 of the plant is to be formed. This fluid is 

 neither wood, nor bark, nor leaf, nor flower, 

 nor fruit, but forms part of each one of these. 

 The blood of an animal is neither flesh, nor 

 bone, nor fleece — yet bone, flesh and fleece 

 are formed from its substance. The falling 

 sap is also a fluid adapted for everything ; 

 it is the material of the fruit and the wood, 

 the leaves and the flowers, the bark and the 

 shoots. It is the blood of the plant and 

 everything in the plant finds therein a pro- 

 vision for growth and food. What a wonder- 

 ful and incomprehensible process has been 

 needed for this purpose ! What activity 

 and what transformations beyond the reach 

 of human science are going on in the crowded 

 ranks of the cells of the apparently quiet 



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