Ill 



HOW TREES GROW 



A TBEE is made up of three important parts — 

 the roots, the trunk or stem, and the leaves. 

 Altogether it is a combination of earth elements, 

 water, and buoyant, invisible gases — the latter 

 comprising about one-haK. If we burn a stick 

 of wopd in the open air, those parts akin to it 

 pass off in the form of gas: the water goes 

 up in invisible steam; that which is left, the 

 ashes, is of the earth earthy. The ashes never 

 comprise more than one-tenth the weight of the 

 dry timber. All the rest is but a vapor and a 

 breath 1 Think of it. 



The alchemist that magically constructed a 

 strong and mighty tree of these primary ele- 

 ments is the leaves. No fairy tale is so won- 

 drous as the work they do. Besides serving as 

 lungs for the tree, each leaf is a tiny laboratory 

 in itself, devoted principally to the manufac- 

 ture of starch. It obtains raw materials from 

 the air and from the soil. The sun furnishes 

 the power. The machinery is the soft green 

 leaf-pulp. 



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