"I will cut a piece of it away, and we shall see that the holes are not on the outside only, but all through the sponge. The sponge is full of holes. Will knows the proper name for these little holes.""Oh yes," said Willie, "teacher told us to call them pores; and as the sponge is full of pores, we say it is porous.""Then I suppose," said Norah, "the sponge sucks up the water because it is porous; the water fills up the holes in it.""Right," said Fred. "Here is a piece of bread. If I stand it in the saucer with only a little water in the bottom, the bread will soon be wet all through.""The bread, like the sponge, is porous," said Norah. "I can see the holes in it.""Yes," said Willie, "but teacher showed us that some things may be porous although we cannot see the pores.""How did he do that? " said Norah.
"He put a piece of lump sugar and a piece of chalk into a plate, with a little red water in the bottom," said Willie. "We couldn"t see any pores in the sugar or the chalk, but we saw the red water go up. That proves that there must be pores in them, and that sugar and chalk are both porous bodies.""Teacher gave us a long word to think about." said Fred. "The word is absorb , and it means to suck up.
