and it to me," said his father, "and I will show you how it can be
done."

He also asked Jonas to hand him the tongs, which were standing by the
side of the fire. He then held the tongs over the sheet of paper, in a
horizontal position, and gently rapped the end of the magnet against
them, letting the end project a little over the tongs. This knocked all
the sand off, and left the bar clean as it was before.

"Now let me see," said he, "what was it that I was going to tell you
next?"

"You were going to show us," said Rollo's mother, "that there are two
different kinds of magnetisms in the two ends of the bar."

"O, yes," said he. "In order to do this, I must poise a needle in a new
way."

He then took up one of the corks which Rollo had put upon the table.
From one end of this cork, he cut off, with his penknife, a round, flat
piece. It was about as large around as a wafer, but somewhat thicker.
He cut a little groove along the upper side of this, and laid the same
needle which he had before used, and which he had put away upon the
corner of the table, into this groove. Then he put the whole carefully
into the saucer of water, which he had previously drawn up towards him.

"There," said he, "we call a cork like that, a _float_; because it is
intended to float a needle upon. Now, you see, the needle being
supported by the cork, and the cork floating freely in the water, the
needle is at liberty to move in any way."

Nathan thought it was a very curious experiment to poise a needle so,
upon a piece of cork,--even without the magnetism. And he watched it as
it slowly moved about, with a face full of interest and curiosity.

The needle swung round a little one way and the other, and finally came
to a state of rest. Then Rollo's father held the magnet in his hands, in
such a manner as to point it towards the needle, and then gradually
brought it down near the water, just by the side of the point of the
needle. The point immediately began to move slowly towards the bar; but
Rollo's father lifted it up suddenly, before the needle had time to
touch it. Then he brought the same end of the magnet down upon the other
side of the point of the needle, and that drew it back again.

"There," said he, "you all see that the point of the needle is attracted
by the bar, whichever side I put it."

They all said they saw it very plainly.

"Now," said he, "I am going to turn the magnet, and bring the other end
of it down to the