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James Watt And The Teakettle
A little Scotch boy was sitting in his grandmother's kit- chen. He was watching the red flames in the wide open fire- place and quietly wondering about the causes of things. In- deed, he was always wondering and always wanting to know.
"Grandma," he presently asked, "what makes the fire burn ?"
This was not the first time he had puzzled his grand- mother with questions that she could not answer. So she went on with her preparations for supper and paid no heed to his query.
Above the fire an old-fashioned teakettle was hanging. The water within it was beginning to bubble. A thin cloud of steam was rising from the spout. Soon the lid began to rattle and shake. The hot vapor puffed out at a furious rate(2). Yet when the lad peeped under the lid he could see nothing.
"Grandma, what is in the teakettle ?" he asked.
"Water, my child--nothing but water(3)."
"But I know there is something else. There is some- thing in there that lifts the lid and makes it rattle."
The grandmother laughed. "Oh, that is only steam," she said. "You can see it coming out of the spout and puffing up under the lid."
"But you said there was nothing but water in the kettle. How did the steam get under the lid ?"
"Why(4), my dear, it comes out of the hot water. The hot water makes it." The grandmother was beginning to feel puzzled.
The lad lifted the lid and peeped inside again. He could see nothing but the bubbling water. The steam was not visible until after it was fairly out of the kettle.
"How queer !" he said. "The steam must be very strong to lift the heavy iron lid. Grandma, how much water did you put into the kettle?"
"About a quart(5), Jamie(6)."
"Well, if the steam from so little water is so strong, why would not the steam from a great deal of water be a great deal stronger? Why couldn't it be made to lift a much greater weight ? Why couldn't it be made to turn wheels ?"
The grandmother made no reply. These questions of Jamie's were more puzzling than profitable,(7) she thought. She went about(8) her work silently, and Jamie sat still in his place and studied the teakettle.
