Materials:

1. A clean jar (either glass or plastic) with a wide opening and a lid

2. a container that will hold water and is small enough to fit upright inside the jar

3. salt, water and a spoon

The Setup:

1. Fill the small container about 3/4 full of water

2. Stir in a couple teaspoons of salt (to taste)

3. Place the lid upside-down on the table or counter

4. Stand the container of saltwater inside the upside-down lid

5. Turn the big jar over and carefully screw it onto the lid, over the water container

6. Put your new solar still in a sunny window for a few hours

*Large plastic bottle, 2 lt Coke bottle will do

*Hot water, tap is good but right out of a coffee maker is better

* Ice

* A small container to hold ice, water and the 2 lt. Coke bottle.

First, set-up an ice bath in the container. Next, place the cap on the bottle and place it in the ice bath. Nothing will happen. Take the bottle out dry it off completly.

Next, take the hot water place it in the 2 lt. bottle and immediately poor it out. Note, you may want to do this twice to bring the bottle up to temperature. Next, after pouring the water out immediately, as quickly as you can, put the cap of the bottle as tightly as possible. Now place the bottle back into the ice cold water bath. In about 15 seconds the bottle will completly collapse.

This demonstrates the power of pressure and heat through a very simple medium….water.

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