TREES AND TKEES. 93 



Biology, botany, chemistry and the laws of light, heat 

 and color can be studied in their growth and structure ; 

 and he who enters this gateway of investigation will 

 find a new and charmed land before him — it may be a 

 wonder-land — but the first step taken will lead to the 

 desire to explore the whole magic domain. As he looks 

 upon that well-proportioned trunk towering into cloud- 

 land, with its wide spreading branches crowned with 

 milhons of shining leaves, he will wish to know how 

 these have been silently gathered, atom by atom, from 

 chaotic inorganic matter and so perfectly arranged and 

 so exquisitely painted — how the cells of root, stem and 

 leaf are formed — the material that enters into their 

 composition — how they multiply and divide and arrange 

 themselves like a big army of little workers to build up 

 the huge citadel and to provide for the perpetuation of 

 its kind. He will wish to know how the millions of 

 root mouths suck the food from the earth and send it so 

 far through such myriads of circling channels to the 

 leaves for digestion and assimilation — how the tree 

 breathes through its countless stomata, leaf -mouths, ex- 

 haling oxygen and inhaling carbon in sunlight, and 

 reversing the process in the dark. He will wish to know 

 why alternate leaves arrange themselves spirally on the 

 stem with mathematical exactness ; why the root seeks 

 darkness and the stem the light, and why leaves are 

 attracted strongly toward the blue and violet rays of 

 light, while the yellow rays assist more in their develop- 

 ment and growth. 



