is to prove what I said to you--that
the air, which is blown out at the nose of the bellows, really comes in
through the valve. Let me see,--I want something to make a smoke."

"Will not paper do?" said Rollo.

"Yes," said Jonas, "here is some brown paper, which will do." So Jonas
rolled it up, and told Rollo to set it on fire, and then, when it was
well burning, to step on it with his foot, and put the flame out.

Rollo did so, and the paper lay in a heap, making a great smoke upon the
hearth, just before the fire.

"Now," said Jonas, "put the bellows upon its edge, by the side of the
paper, so as to have the valve near the smoke, and then hold still a
minute, until the smoke comes up steadily by the valve."

When this was done, Jonas told Nathan to take hold of the nose of the
bellows, to steady it, so that Rollo could blow. He then directed Rollo
to lean the bellows over a little towards the smoke, so that the moving
side should not rub upon the hearth, when he began to blow.

"Now," he continued, "if you work the bellows, you will see that the
smoke will be drawn in through the valve, and then will come out through
the nose."

This experiment succeeded perfectly well, only just in the midst of the
interest that they felt, in seeing the smoke come pouring out through
the nose, they heard a bell ring at the house. They knew at once that
this bell was for Rollo and Nathan; and so the two boys jumped up from
the hearth, and ran out to see what was wanted. They went through the
shed into the barn, and thence on till they came to the great barn door,
where they had come in. There Rollo stopped,--for he did not like to go
out into the snow,--and asked Dorothy, who was ringing the bell, what
she wanted.

"Where's Nathan?" said Dorothy.

"He's here with me," said Rollo. Nathan was coming along, as fast as he
could, through the barn.

"Do you want us?" said Rollo.

"No," said Dorothy, "only we did not know where you were. You may stay
half an hour more, and then it will be nearly dinner time."

Dorothy then went in, leaving the boys at the great barn door. The door
opened in such a direction, that the wind did not blow in; and Rollo and
Nathan looked out for some time, watching the falling snow, and
listening to the wind, as it roared through the tops of the trees. At
last, when they began to think of returning to the shop, Rollo said,--

"O Nathan, let us go and hide, and then Jonas will not know where we
are