ide of the board, and was attempting to drive it in there, as if
he supposed he could split the board _across_ the grain.

"Why, Nathan," said Rollo, "that isn't right. You can't split it
across."

Then he put the wedge into the end, where it ought to be put, and set
Nathan to driving it. _Now_ it began to split at once; though Nathan
could not see why the board should not split one way as well as the
other.

Rollo himself did not understand it very well. Nathan asked him why it
would not split the other way, and he said that that was _across_ the
grain. But when Nathan asked him what he meant by _grain_, he could not
tell.

He took up the wood and examined it, and observed little lines and
ridges, running along in the direction in which it would split; but at
the ends of the board, where it had been sawed across the grain, it was
rough. He determined to ask Jonas about it, or his father.

He then went to work, and made the wedges and a little beetle for
Nathan. He made Nathan's beetle smaller than his own, because Nathan
was not strong enough to strike hard with such a heavy beetle. He did
not get it done in season to use that day; but, the next day, he and
Nathan sat down upon the shed floor, and spent an hour in splitting up
the boards. They split them all up into good, fine kindling wood. Then
they piled the pieces up in a neat pile, and then brought Dorothy out to
see them.

Dorothy seemed very much pleased, and promised the boys that, the next
time she baked pies, she would kindle the fire in the oven with their
kindling wood, and then she would bake them each a little apple
turnover.

* * * * *

That evening, just before Rollo went to bed, he asked Jonas if he could
tell him why boards would only split _along_ the grain.

"Yes," said Jonas, "I think I can tell you. But do you know what the
grain is?"

"No," said Rollo, "I don't know any thing about it."

"You know that boards are made from the stems of tall trees."

"Yes," said Rollo.

"Well, now when trees are growing, there are little channels running up
and down from the roots to the branches."

"What are they for?" said Rollo.

"They are for the sap. The sap flows up and down in them. But then there
are no channels across from one side of the tree to the other, because
there is no sap to go across. The sap all has to go up from the roots to
the branches; and so the channels must all be up and down the tree.