EXPERIMENTS.
When Jonas had finished nailing down the corner, he said, "Now there are
several experiments, which we can perform with the bellows. I will be
the professor, and you two shall be my class in philosophy, and I will
direct you how to make the experiments.
"First," said Jonas, "you, Rollo, may take hold of the nose of the
bellows with your hand, in such a way as to put your thumb over the end
of it, to stop it up, and then let Nathan try to blow."
Rollo did so, and Nathan tried to blow. He found that he could open the
bellows very easily; but when he attempted to press the sides together
again, he could not. He crowded the handle belonging to the upper side
down, as hard as he could, but it would not move.
"What makes it do so?" said Nathan.
"The air inside," said Jonas. "We have stopped up all the places, where
it could get out. The valve stops itself. Rollo stops the nose with his
thumb, and I have nailed the leather down close, about all the sides.
And so the air can't get out, and that keeps you from bringing the sides
together again."
Nathan tried again with all his strength. The sides came together very
slowly.
"They're coming," said he.
"Yes," said Jonas. "They come a little, just as fast as the air can leak
out through the little leaks all around."
"I thought you stopped all the leaks," said Nathan.
"Yes," replied Jonas, "I stopped all the real leaks, but still I can't
make it perfectly tight. Some air can escape between the leather and the
nails all around, and just as fast as it can get out, so fast you can
press the sides together, and no faster."
Here Nathan tried again with all his strength; but he could only bring
the sides together very slowly.
"Now comes the second experiment," said Jonas. "While Nathan is trying
to press the two handles together, you, Rollo, may run your finger into
the hole, and push up the valve a little."
Rollo did so. He pushed up the valve a little with his finger, and that
allowed the air to escape through the opening. The consequence was, that
the bellows collapsed at once under the pressure which Nathan was
exerting upon them.
"There," said Jonas, "you see that when the air is kept in, you cannot
bring the sides together; but when I let the air out, then they come
together easily."
"Yes," said Nathan; "do it again, Rollo."
So they performed the experiment again. Nathan pulled the handles apart
wide, while Rollo kept his thumb over the nose, to keep the air from
issuing through. Then Nathan tried to press them together; but he could
not, until Rollo put his finger under, and pushed up the valve a little,
and then they came together again very easily.
"The air is a real thing, I verily believe," said Nathan.
"Yes," said Rollo, "I know it is. And now for the third experiment,
Jonas."
"The third experiment," said Jonas, "is this. Turn the bellows bottom
upwards, and try to blow."
Nathan did so. He found that he could work the bellows easily--too
easily, in fact; but they did not blow.
"Hold your hand opposite the nose, and see if any wind comes," said
Jonas.
They did so; there was no wind, or rather scarcely any.
"The reason is," said Jonas, "that, when the bellows are bottom upwards,
the valve hangs down off from the hole all the time, and lets the air
all out through the hole in the side; and it can come out more easily
there than through the nose, and so it don't blow well."
"Well, Jonas," said Rollo, "that's a pretty good experiment; but what is
the next? Let me try the next. Nathan, it is my turn."
"The next experiment, which is the fifth,----"
"No, the fourth," said Nathan.
"The fourth, then," said Jonas, "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."
"Well," said Nathan, "we will."
The boys accordingly began to look about the barn for a place to hide.
It was a large barn, with stalls for oxen and cows, and cribs for
horses, and one or two calf-pens. Then there was a granary in one
corner, and a tool-room near it, and lofts and scaffolds above. The boys
found plenty of places to hide in, and it took them some time to decide
which to choose. At last, they found a good warm place, by some bundles
of wheat straw, up in the barn chamber; and they amused themselves by
choosing out large straws, and making tubes of them to blow through.
They called them their _bellows_.
They entirely forgot that they were hid from Jonas, for nearly half an
hour; and then Rollo proposed that they should creep softly down, and
see what Jonas was about. So they went down stairs on tiptoe; Rollo
first, and Nathan following. They crept softly along to the door leading
out into the shed, through which they had to pass in order to get to
the shop; and Rollo was going to open this softly, when, to his
surprise, he found it fastened.
"Why, Nathan," said he, "this door is fastened."
"How came it fastened?" said Nathan.
"I don't know," said Rollo, "unless Jonas fastened it. I think he must
have finished his work, and gone into the house; and so he has fastened
this door."
"And now he won't come and find us," said Nathan.
"No," said Rollo, "and we must go out the front door. And I don't care
much," he continued, "for it is pretty near dinner time."
The boys then went back to the front door of the barn, and, to their
surprise and alarm, found that fastened too.
"What shall we do?" said Rollo; "Jonas has fastened us in." As Rollo
said this, his face assumed an expression of great solicitude, and
Nathan began to cry.
"Don't cry, Nathan," said he; "we can find some way to get out. But I
don't see, I confess, what made Jonas lock us in."
The truth was, that Jonas did not know that the boys were in the barn
when he fastened it up. As they did not come back after they had gone to
answer the bell, he supposed that they had gone into the house; and when
he was ready to come in himself, he shut and fastened the back doors of
the barn, as he usually did when he left the shop. He then came around
to the front barn door, and although that was on the sheltered side, so
that the wind did not blow in, he thought it possible that the wind
might change, and so drive the snow in upon the barn floor; and
therefore, to make all safe, he thought that he would shut them, too. He
accordingly shut the great doors, and put the fid into the staple. The
fid is a wooden pin, to be passed through the staple when the doors are
shut, to fasten them. The doors cannot be opened again until the fid is
taken out.
Rollo went all around the barn, trying to find some place where he could
get out; but he could not find any place at all.
"Let us go up stairs," said he, at length, to Nathan.
"O, it will not do any good to go up stairs," said Nathan. "It would
kill us to jump out the window."
"I know we can't jump out the window," said Rollo, "but perhaps we can
find out some way to get down. O, there is a ladder; I remember now,
Nathan, there is a ladder. We can get down from the window by the
ladder."
"I shall be afraid to go down the ladder," said Nathan.
"O no," said Rollo, "I will go first, and see if it is safe."
By this time they had reached the barn chamber. There was a window in
it, with glass, over the great barn door; but Rollo could not get it
open. He told Nathan that, if he could only get it open, and could find
a long pole, he could reach it down, and knock the fid out, and so open
the great doors. But, with all his efforts, he could not raise the
window.
There was another window, which had no glass, but was closed by a wooden
shutter, which opened upon hinges like a door. Rollo said he meant to
open this window. Now, it happened that this window was upon that side
of the barn which was exposed to the wind and storm; and, the moment
that Rollo had pushed open the shutter a little way, the wind forced it
instantly from his hand, and slammed it back against the side of the
barn, with great violence. It almost pulled Rollo himself out of the
window.
Nathan looked frightened. Rollo himself looked somewhat astonished at
such an unexpected effect; but presently said,--
"Well, Nathan, I rather think that, if you had had hold of that shutter,
you would have thought that air was a real thing."
"O, that was the _wind_, Rollo; that was the _wind_," said Nathan.
Rollo did not answer, but went to the ladder, which was standing up
against the hay-loft. It was a pretty long, but yet a very light ladder;
and Rollo and Nathan succeeded, after some difficulty, in getting it
down, and in running the end out of the window. When the lower end
reached the ground, the upper end was two or three feet above the bottom
of the window; so that Rollo could easily get upon it to descend. The
wind and storm, which raged with great violence, were somewhat
terrifying; but he knew that the ladder was secure, the upper part being
confined in the window; and so he resolutely descended. When he had
fairly reached the ground, he looked up, with an expression of great
satisfaction upon his countenance, and said,--
"There! now, Nathan, for your turn."
But Nathan was afraid to venture; and Rollo himself was half afraid to
have him make the attempt. While they were standing in this perplexity,
Rollo heard a voice behind him, calling out,--
"Rollo."
Rollo turned, and saw Dorothy standing by the door.
"What are you doing, Rollo?" said Dorothy.
"I am trying to get Nathan out of the barn," said Rollo.
"How came he in the barn?" said Dorothy.
"Why, Jonas locked us in, and I had to come down the ladder; but Nathan
is afraid, and I can't get him out."
"Why don't you go to the door, and let him right out?"
"O," said Rollo, laughing, "I never thought of that. Go down, Nathan,"
he continued, "to the door, and I will go round and knock out the fid."
So Nathan went down, and Rollo, meeting him there, knocked out the fid,
and released him from his imprisonment.
QUESTIONS.
What was the first experiment with the bellows, described in
this chapter? Why could not Nathan press the two sides of the
bellows together, while the nose was stopped? What was the
second experiment? What was the effect produced by turning the
bellows bottom upwards, as in the third experiment? What was the
fourth experiment? What was the use of the smoke of the paper?
How were the experiments interrupted? What evidence did Rollo
and Nathan have that the air was a real substance, when in the
barn chamber?