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Coral Castle by Aaron and Tevi

We're really into exploring the science of places like the Egyptian pyramids, or England's Stonehenge, so we thought we'd investigate a science mystery in our own town! Our DragonflyTV question: How was Florida's amazing Coral Castle built?

What did we do?
First, we brushed up on the Coral Castle's history. It was built by a Latvian immigrant named Ed Leedskalnin between 1918 and 1946, and consists of over 1,000 tons of coral. Somehow, he moved all that coral by himself! The castle has weird and fascinating features like a stone rocking chair, and cool statues of the moon and Saturn. We wanted to figure out how Ed moved all of these massive stones! From our investigating, we know he used simple tools. We built a similar set-up to Ed's, using a fulcrum and lever. Then we built a tripod with a block and tackle system, also based on Ed's original design, to see if we could lift huge limestone blocks of the ground.

What did we find out?
For a lever, we got a long piece of lumber. We used a log as a fulcrum. We found a big piece of scrap limestone in the area, and tried to move it with the lever. It took some work, but if we kept the boulder near the fulcrum, while we got on the other end of the lever as far from the fulcrum as possible, we could roll the boulder along. Then we tried picking up the boulder using the block and tackle. It wasn't as easy as we thought it would be. To give us a little more advantage, we added a winch. Using the winch and block and tackle together, we lifted a 2000 pound boulder off the ground with our own strength!

What can you do?
  • Simple machines make great toys! Look for simple machines like levers, pulleys and gears, inclined planes, wheels and axles, and wedges among your toys. How many can you find?
  • A simple kitchen can opener has at least three simple machines all wrapped into one. Next time you open a can of soup, look for the three machines and determine what each one does to help you open the can!
  • Design a machine that consists of two or more simple machines, and completes a specific task. It could be a gravity-powered door opener, or whatever you like. After you design it on paper, see if you can actually build it and make it work!
  • Use this physics investigation as a science fair project idea for your elementary or middle school science fair! Then tell us about it!
more resources
More on simple machines.

Go to the DFTV Boards, and tell us about your science investigation.
whiz quiz
What is the world's largest living organism?

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