Just before school broke up for a couple of weeks of holidays, the children became really interested in optical tricks. Recently, they have also been getting really excited about Halloween. They have been asking about whether there were any cool optical tricks which they could use to haunt their friends with and when I told Roy about this, he suggested we learn to do a small scale version of a famous Victorian Theatre Trick - Pepper's Ghost. Now, we have perfected the act and are ready to teach all our online friends!
Pepper's Ghost first appeared on stage in 1862 when it was performed on Christmas Eve as part of Professor Pepper's act. A 'ghost' appeared out of thin air on stage, interacted with the characters and then simply disappeared again, as if back into thin air. The audience was stunned by the spectacle and some believed that Pepper had really found a way to summon spirits! Of course, he hadn't, it was a simple illusion, but the fact that it was done on a lit stage in front of an audience was magic. Yet it is actually a very simple 'trick' and one which anyone with a strong light, a dark spot, a mirror and a sheet of clean glass or perspex can do!
There is a really simple, fantastic introduction to the illusion of Pepper's Ghost on the Naked Scientists Website. Click here to see their version. You might like to try their version before attempting Roy's smallscale, authentic version!
You Will Need:
- Two boxes. Roy used a shoe box and a larger box.
- Black paint and a paintbrush
- A pair of scissors, a craft knife and an adult to help you with cutting
- Stickytape or masking tape
- Bluetac
- A strong, directed light source, like a torch.
- A piece of very clean glass or perspex
- Something to reflect. You can use a doll, a printed picture, even an iPod or iPad playing a video would work! If you use a doll, like Roy did, you will want some toothpicks and corks if the doll won't stand up by itself.
- A mirror
- Some patience.
Method:
- Paint the inside of your boxes black and let them dry. Roy made his in a hurry and didn't do this step, but the trick will work better if the boxes are painted black inside first.
- Cut an opening in the top of the larger box. You want it to be a little bigger than the mirror you plan to use. Think of the opening you make as the 'Orchestra Pit' for your little theatre.
- Using stickytape, stick down the top of the box so that you have a firm, flat stage area.
- Roy used two small dolls in his Pepper's Ghost, one standing on the stage and one underneath to be the 'ghost'. To make them stand upright he cut a cork in half and pushed a toothpick into the cork. He then very carefully pushed the toothpick through the dolls clothes. This made a simple stand for holding the dolls in place and making them stand up all on their own.
- Make sure your glass and mirror are very clean. If there are fingerprints or dust, clean them off.
- Put one doll under your stage area.
- Take your mirror and, using bluetac, secure it to the end of your 'orchestra pit'. You want it to be angled slightly upwards, at about 45 degrees so that it bounces the image of the doll up towards the glass. Roy used a little mirror with a blue surround. Ideally, your mirror will not have any frame, but one like Roy used is just fine.
- Using the craft knife or scissors, cut the shoebox into two pieces. You want one piece to be about the same size as your 'stage area'. Discard the second piece.
- Turn the shoebox upside down so that you can put the glass in place. Roy used the glass out of a picture frame.
- You will be putting the glass in at an angle of about 45 degrees - leaning forward, tilting towards the opening of the stage and just behind the very front of the stage. Use bluetac to hold it to the 'top' of the box. Make sure that it is securely held by the bluetac.
- Stand your second doll on the stage.
- Carefully turn the box the right way up and sit it over the top of the stage. You want to put it over the top of the second doll so it appears behind the glass.
- Find a dark place and turn off the lights. You might want to wait until it is night time for the best effect.
- Point the torch at the doll under the stage and look through the opening in the front of your top box. If everything is positioned right you should see a ghostly reflection of the doll under the stage, reflected first on the mirror and then on the glass. If you can't see it, try adjusting the torch and the doll you are reflecting until it works. If it is really dark, you might want to ask another friend to hold a light on the stage itself, otherwise you might only see the ghost!
- You can also use other items for your ghost - Roy made a Humpty Dumpty as well!
- You might want to make curtains to hide the sides of your glass. When the Victorians were originally using this trick, the edges of the glass would have been covered. This would make it very difficult to see the glass, and the trick would be even more difficult to work out!