What is needed

• Knife, fork, spoon and some free time - like at one of those big family dinners where you can't get a word in edgewise.
• Wooden table

The Spoon: What to Do

• Hold a spoon up near to your face, and look at the back of the bowl. You will see your reflection in the spoon. It should be small, and right side up.
• Now, take the spoon and hold it up near to your face, and look at the front of the bowl. This time, you will see your reflection, but it will be upside down.
• The plot thickens. Hold the spoon as close as you can to your face. The closer you can hold it (while still looking into it) the larger the image of what you are looking at will appear. If you work at it, you can use the spoon to produce a very magnified image of your nose. (It's not a pretty sight viewed up close, trust me.)

The Spoon: What is Happening

OK, here's the scoop: the spoon is a mirror, but because of its shape, it's either a convex mirror (if you look at the back of the bowl) or a concave mirror (if you look at the front.) These kinds of mirrors disort the images that they make. A convex mirror - like the back of the spoon - makes the image smaller and right side up. A concave mirror - like the front of the spoon - makes an image that can be small or large, and right side up or upside down. The key is how close you are to the mirror. The image is usually upside down, and the closer you are to the mirror, the larger the image, up to a certain point. Beyond this point, the image flips right side up. Concave mirrors are the kinds of mirrors that get used in telescopes.

The Knife: What to Do

• Place the edge of the knife blade next to the table, tipped sharp edge up, and look at a reflection of the table in the knife blade. If there is something around with letters on it, place this below the knife. Reflections of letters are very cool, and you can fool with them for hours.
• Try seeing how the reflection changes as you change how you hold the knife.

The Knife: What is Happening

Basically, you are just using the knife as a small mirror. As you look at the reflection of things in the mirror, you can explore how they are reversed and changed. It's also fun to make a pattern by looking at something directly with its image in the knife right above it.

I have been known to entertain myself this way at a Chinese restaurant (with a placemat with lots of words and pictures) for the better part of an hour.

What to do: The Fork

• Hold the fork gently between your thumb and forefinger, at the narrowest part.
• With your other hand, pinch two of the tines of the fork and "ping" them.
• Press the end of the fork (not the tines) gently against the table. Do you hear a tone?

The Fork: What is Happening

If you have good stainless forks, or, even better, silver, they will vibrate very nicely. Pinging the tines starts a good vibration. Now, when you touch the end of the fork to the table, the table acts as a sounding board - and makes it so you can hear the vibration. It is playing the same role as the body of a violin or other stringed instrument.

Other Things to Try

If you can get a good vibration on your fork, try putting the tines in your water glass (best if there is no ice.) This makes a nice effect. And you might try the images in different spoons; soup spoons in particular let you get a very up-close-and-personal view of, say, the inside of your nose. This is a fascinating way to spend dinner, especially if you share your observations with others at the table.