98 
THE STORY OR THE OAK TREE 
Does it not seem strange that in a shovelful of soil, 
nearly half of the total volume is pore-space, this air¬ 
space between the particles of earth? 
The other day I watched the gardener plant some 
shrubs. First he dug his hole and put in a bush; then, 
when he had filled in the earth all round, he stamped it 
gently down with his foot. After he had watered it well 
he sprinkled loose earth over the firm soil; he told me 
this loose earth kept the water from evaporating into the 
air. He said that plants get their moisture from two 
sources, from the rain which falls from above, and from 
the ground water which rises from below—the water men 
find when they dig wells. It is a curious fact that when 
water finds tiny cracks or spaces in solid earth or rock, 
it is drawn upward to the soil where the roots of plants 
can drink it. The cracks must be very fine, though, 
finer than a hair, or the water will not follow them; that 
is why, the gardener said, that he scatters loose earth or 
straw over the trampled earth around his newly planted 
bushes. In this loose earth the cracks are too coarse to 
draw the water up where it will pass into the air, and 
so it remains in the soil where the plants need it. 
And now it is time to speak of one more link in the 
Web of Life, a strong link and an important one, al¬ 
though it is made by creatures we look down upon as 
the lowliest of all living things. There is a humble crea- 
