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B. Ahoy! You are right! The paddle wheels were indeed turned by steam power. The power of steam fascinated scientist and inventors for hundreds of years. Steam is a strong form of energy. We can see steam's power by simply boiling water in a covered pot. The steam will make the lid go up and down. If we use a tight lid, the steam would not be able to escape making the pot explode! |
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b) The steam travels through pipes to the rocking cylinder, where it forces a piston to move up and down. c) The piston moves the connecting rod. This in turn pushes or pulls the crankshaft, making paddlewheels turn. d) This rotary motion propels the ship along. |
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You can go see this paddlewheel at the Hyde Street Pier in San Francisco. |
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At first, a paddlewheel ship had sails in case the engine broke down or it ran out of coal. The main problem with a steam paddlewheeler is that coal stations were scarce and very expensive. Also, steamers needed to stop on an average of ten times to refuel on a long trip. That's time consuming! As steam engine technology improved and coal stations became more plentiful, steam ships took over clipper ships.
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a) The coal fire in a boiler heats fresh water to produce steam.
