Can you sit on an egg without breaking it?

Find out in this experiment.

4 eggs
small pair of scissors
masking tape
several large books about the same size (e.g., encyclopedia volumes)
weight scale

1.At the sink, gently break each egg at the narrow end by tapping it sharply with a spoon. Peel back a little of the broken shell and empty the contents.

2. Stick a piece of masking tape around the middle of each shell to prevent it from cracking when you cut it.

3.Carefully cut around each eggshell, through the masking tape, so that you end up with four half-shells of equal size, with level bottoms.

4. Place the eggshell domes on a smooth, clean floor or tabletop in a rectangle slightly smaller than your books.

5. Lay a book on the eggshells. Then another. Do the shells crack? Keep adding books. Important: In order for this experiment to work well, you must make sure the shells don't move when you add each book. If there is any twisting or pushing on the shells, they will break more easily. The weight must all be placed straight down on top of them.

6. Continue adding books until the shells crack. Weigh all the books to see how much weight the eggs could take. It should be much more than the weight of a chicken!

The dome shape of each shell distributes all the weight evenly and minimizes stress and strain. Demonstrations at the Ontario Science Centre in Toronto have shown that a single hen's egg can support 90 kg (200lb)!