60 FIRST STUDIES IN PLANT LIFE 



that were never alive. The plants turn these dead 

 things into living food that the animals can eat. The 

 wheat plant turns these dead things into bread, which 

 is the staff of life for man. Follow the steps clearly 

 in your mind — from the dead stuffs up to the body of 

 man. Sometimes we make use of the lower animals 

 to help us to get the living food we need. The grass 

 eats the dead earth-foods and air-foods ; the cow tm-ns 

 the grass into milk ; and we turn the cow's milk into 

 human bodies. You see, then, how much depends on 

 the leaf. Our lives depend on it ; the lives of our 

 horses and cows and dogs depend on it. The leaf is 

 as useful as it is beautiful. 



6. The leaf cannot travel to seek food. Now, 

 this wonderful worker — the leaf — is not able to travel 

 in search of food : it must stay in one place. It cannot 

 fly like a swallow, seeking its food in the air. It has 

 to wait for the food that happens to come floating by 

 on the air-currents, just as the sea-fiower — the 

 anemone — has to wait till the current of water brings 

 some little shrimp or shell-fish within its reach. 

 When you remember how little carbon there is in the 

 air,* you will see that a great tree has need of many 

 leaves to catch food for it ; for _you must never forget 

 that every living part of the tree, from the topmost 

 twig to the lowest root, lives on the food that the leaf 

 makes. 



7. We must now look inside the leaf, and see how 

 it is able to do this wonderful work. And here you 

 must allow me to look through the microscope and 

 tell you what I see. 



♦ In 2000 cubic feet of air there is only one cubic foot of carbon dioxide. 



