书城教材教辅科学读本(英文原版)(套装1-6册)
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第23章 第一册(23)

Clay is a mineral; it is dug out of the ground. Dry clay is porous; it absorbs water. Moist clay is not porous; it will not absorb water. Moist clay is pliable. We can mold it into any shape we please.

Lesson 12

Clay-Its Uses

"I never knew till today," said Fred, "what a useful thing clay is. It is useful because it is pliable.

"You know we made a saucer and a basin with our pieces of clay?""Yes," said Norah, "here they are. I put them on the shelf.""Do you know," he said again, "that all our saucers and basins, and cups and jugs, and plates and dishes, are made of clay too?

"Yes, and so are the bricks and tiles and chimney- pots for building our houses, the drainpipes for taking away waste, and the flowerpots for our gardens.