His father did not answer, but immediately raised the bar and put it
down upon the other side of the point, and then the point began to move
away back again; being evidently driven away from the large end of the
magnet, on whichever side it was presented.
Then Rollo's father reversed the magnet again; that is, he brought the
smaller end towards the needle as at first. The point of the needle was
now attracted, that is, drawn towards the magnet; and then when he
changed it again, and brought the large end to the needle, it was always
_repelled_; that is, driven away again.
"Now you see," he said, "that the small end of the magnet attracts the
point of the needle, and the large end drives it away. That shows that
the magnetism in the two ends is of two different kinds.
"And now," he continued, "there is one thing more which is remarkable
about it; and I want you to observe it very carefully. You see," he
says, "that the small end of the magnet attracts the point of the
needle. But if I try it now upon the other end of the needle, where the
eye is, it will _repel_ that, just as the large end of the magnet repels
the point."
He tried it, and the result was just as he had said. And he repeated the
experiment in a great many ways, and they always found that the large
end of the magnet would draw the eye of the needle towards it, and drive
the point away; and the small end of the magnet would draw the point of
the needle, and drive the eye away. This proved, as Rollo's father said,
some great difference between the magnetisms of the two ends. "And you
see," he added, "that it is a difference in _kind_, not merely a
difference in _degree_."
"But one thing seems strange to me," said Rollo's mother, "and that is,
that both ends of the magnet don't attract the point of the needle, just
as both of them attracted the nail."
"And the sand," said Rollo.
"Yes," added his mother. "When you brought both ends of the magnet, one
after the other, to the nail, they both attracted it."
"And so they did the needle which hung down by the thread," said Jonas.
"Yes," said Rollo's mother; "but now this needle, that is floating upon
the water, is half attracted, and half repelled."
"The reason is," said Rollo's father, "that the needle, that is floating
upon the water, is a magnet itself, and has two magnetic poles; but the
sand, and the nail and the needle that Jonas held up by the thread, were
not magnets. They were only common pieces of iron and steel."
"Why, father," said Rollo, "that was the very same needle; you laid it
away upon the corner of the table."
"Yes," said his father; "but it was not a magnet _then_."
"When?" asked Rollo.
"Why, when Jonas held it up by the thread."
"And is it a magnet now?"
"Yes," said his father. "We will see if it is not."
Public-domain text, read in full here on John Shaqi.
Reviews
Reviews
No reviews yet
Be the first to share your thoughts on this work.
Join the Discussion
Join the discussion
Sign in to leave a comment or review.
Sign InorCreate an account