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the story or thr oak trrr 
the spokes of a wheel. These streaks of wood are harder 
than the pith, and they are called pith rays, because they 
glance out from the pith as rays stream out from the 
sun. When foresters saw a log this way, the saw, as it 
runs through the center of the tree, will cut the same way 
the pith rays run; that is parallel with the pith rays. The 
pith rays run in wavy lines, so boards cut from the center 
along these rays will show wavy lines or streaks. In oak 
timber these shiny streaks are called “silver sheen;” the 
wood cut in this way is known as quartered oak and is 
the choicest timber of the tree. Perhaps your mother 
has a dining room table or a library table made of quar¬ 
tered oak; look at its smooth polished surface and trace 
the beautiful pattern of the “silver sheen.” 
And now that you understand how the stem is built— 
bark, cambium, sapwood and pith—it is time to speak of 
something marvelous, something the tree does which has 
puzzled wise men for a long time, and puzzles them still. 
There are men, great scientists, who spend their lives 
studying plants, plants of all kinds, high and low, from 
the lichen that grows on the rock to the noblest oak that 
ever spread its leafy branches to the sun. The study of 
plants is called botany, so these men are known as bot¬ 
anists; and little by little, as the centuries go by these 
botanists have coaxed from Mother Nature her secrets. 
They have had to be patient, because Nature guards her 
