It was a pretty custom in fairy-land that when a fairy baby cut its
first tooth, the mother's friends should make the little one some pretty
present.

When Nerthus, the mother of the infant Fro, looked into its mouth and
saw the little white thing that had come up through the baby's gums, she
went in great glee and told the glad news to all the other fairies. It
was a great event and she tried to guess what present her wonderful
boy-baby should receive.

There was one giant-like fairy as strong as a polar bear, who agreed to
get, for little Fro, a creature that could put his nose under the sod
and root up the ground. In this way he would show men what the earth,
just under its surface, contained, without their going into mines and
caverns.

One day this giant fairy heard two stout dwarfs talking loudly in the
region under the earth. They were boasting as to which could beat the
other at the fire and bellows, for both were blacksmiths. One was the
king of the dwarfs, who made a bet that he could excel the other. So he
set them to work as rivals, while a third dwarf worked the bellows. The
dwarf-king threw some gold in the flames to melt; but, fearing he might
not win the bet, he went away to get other fairies to help him. He told
the bellows dwarf to keep on pumping air on the fire, no matter what
might happen to him.

So when one giant fairy, in the form of a gadfly, flew at him, and bit
him in the hand, the bellows-blower did not stop for the pain, but kept
on until the fire roared loudly, as to make the cavern echo. Then all