"Yes, dear, I put the kettle there myself," said Fred. "I wanted you to notice it, for we are going to have a talk about the steam now.
"What would happen if we left the kettle on thefire?"
"The water," replied Norah, "would all boil away, and the kettle would be left dry.""But what does that mean?"
"The water would be changed into steam," said Norah.
"I think," said Fred, "I had better explain it as teacher did. He says that steam is only water in another form. The heat breaks up the water into such extremely small particles, that they are lighter than the air itself. They therefore rise in the air and mingle with it.""But what becomes of it in the air, Fred?""The air is very porous," replied Fred. "It absorbs into its pores these little floating particles, just as water absorbs salt.
"You have seen mother hang out the wet clothes on washing day, and you know that after a time she is able to take them in quite dry. What has become of the water? I will tell you. The water in the wet clothes on the line has been broken up into tiny particles-not of steam, but of something like steam. We call it vapor.