Rollo and Nathan were exceedingly pleased with this plan and even Rollo's mother looked somewhat gratified.It cost low roofing slope is thickest on all the edges and corners, said Rollo.This bar is what they call a magnet, said he but all the magnetism is in the two ends.How cost low roofing slope shall we do it? asked Rollo, looking up with a faint and doubtful smile.Some of Jonas's work, I suppose.She began to look cost low roofing slope into her needle book for the needles and thread, while Rollo went for the sand box.Yes, said his mother and the sand forms little black bristles, pointing off in every direction.Now you see, from all this, added Rollo's father, that when a magnet touches a piece of steel, like a needle, it immediately makes it a magnet itself that is, it makes the two ends magnetic, one having one kind of magnetism, and the other the other kind and then, if you take two magnets, and bring cost low roofing slope those two poles which have the same magnetism together, they repel one another and if you bring those together which have different magnetisms, they attract each other.No, said his father.Now, Nathan, cost low roofing slope exclaimed Rollo, running up to him, and seizing the sand box, you are a very naughty boy.Now, said he, I am going to turn the magnet, and bring the other end of it down to the point of the needle and if the magnetism at this end is the same with that in the other, the point of the needle will of course be attracted by this end too.He told me, too, that if I had a knife, and would rub my knife on the cost low roofing slope magnet, the knife would attract, too and so I did rub it, and I found that my knife would attract the nail, though not very strong.It was quite a small story book, and he had been reading it some time, and so he had got to the end.