Tricky Picture

Ever wanted to lock-up your brother? Well you can, using a thaumatrope! A thaumatrope can make two images appear as one. For example a picture of a cage and a picture of your brother will turn into a picture of your brother in a cage!

Australian Curriculum links

  • Science > Physical Sciences > Year 5 > ACSSU080

You'll need

  • figure-eight pattern (draw your own or download ours below)
  • scissors
  • colouring pencils
  • pen, pencil or straw
  • glue or tape

Try this

  1. Cut out the pattern and fold the paper on the dotted line.
  2. Glue or tape a stick (pen, pencil or straw) inside the folded paper making sure it is in the middle with one end against the fold and the other end poking out the bottom it should look like a lollipop.
  3. Hold the stick between the palms of your hands and twist it slowly so the paper flips from one picture to the other.
  4. Look at the pictures of the lion and its cage. Think of two other pictures that go together.
  5. Trace and cut out a new pattern.
  6. Draw your two pictures on the paper, making sure the paper fold is at the top of each picture.
  7. Test out your pictures by taping the paper to a stick as above.

Further investigation

How fast do you need to spin the thaumatrope before the images appear as one? Think of two pictures that go together to make more another thaumatrope.

For example:

  • a bird and a nest
  • a tree with branches and leaves
  • a rocking horse and a person sitting side-ways
  • flowers and a vase
  • sunglasses and a cat
  • a book with blank pages and words
  • an animal and its habitat

What's happening?

This type of toy is called a thaumatrope. A thaumatrope uses the principle of persistence of vision to create an optical illusion.
When you look at a picture, an impression of the image is retained by your brain for about 1/20 of a second after the object is gone. When you see two pictures in quick succession, like the two pictures of the thaumatrope, your brain continues to see both images after each has disappeared. Because the thaumatrope keeps spinning, the two pictures appear to merge together as one image.

Real world links

Thaumatropes were common toys in the 1800’s. They provided animated entertainment before modern cinema was invented.