In this way a little bit of rain, or dew, lasts a long
time. Come out now, and I'll show you something you perhaps have not
noticed."
Daddy took Hal and Mab to the garden, and with a hoe he pointed to a place
around Hal's corn stalks where the dry ground was hard, and baked by the
sun.
A few strokes of the hoe and Daddy Blake had turned up some of the
underlying earth. Hal and Mab saw that it was darker in color than that on
top, and when they put their hands down in it the earth felt moist.
"What makes it?" asked Mab.
"Because the underneath part of the ground held the moisture in it. The
top part was baked dry and the moisture had all gone away--evaporated in
the sun, if you want to use big words, just as water dries in your hands
after you wash them, even if you do not soak it up with a towel."
"Does a towel soak up water?" asked Mab. "I thought it just wiped it off
our hands."
"No, the towel is like a sponge," said Daddy Blake. "The fuzzier the towel
the more like a sponge it is. Each little bit of linen or cotton, is
really a tiny hollow tube--a capillary tube it is called--and these tubes
suck up the water on your hands as the same fuzzy capillary tubes in a
piece of blotting paper suck up the ink.
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