Push a pencil through a bag of water…without spills!

Push a pencil through a bag of water…without spills!
Children’s Corner


There are literally hundreds of thousands of magic tricks that exist today, each of which have their distinct subtleties or presentations. The majority of these tricks, however, can be reduced down to single-word effects like disappearance or transformation.

One popular effect created by magicians is penetration – the idea of piercing or cutting an object or person and then restoring the object/person to its original state. You probably think you haven’t seen such a trick before but one of the most famous illusions in the world is based on this effect: sawing a lady in half.

In this trick, a person is placed inside a large box horizontally. The magician then slices her with large metal blades, leaving her apparently sawn in two or more pieces. Yet, with a magical gesture the assistant rises from the box unharmed.

There are plenty of versions of this trick – even some with clear boxes – all of which aim to make it seem even more impossible. It’s unclear as to when this illusion started being performed but some sources say a magician named Torrini may have performed the first version in front of Pope Pius VII in 1809 – although many historians question this claim. Regardless by the early 20th century, the trick was being performed in different countries across the world from England to America, and has developed into the amazing illusion we see today.


While it would be a cool trick to learn, starting off with this when training to be a magician might not go down well with your family – especially if one of them is in the box! Instead, there’s another great penetration effect you can do at home that will keep people on their toes. All you need is a plastic bag (one you might keep your sandwiches for lunch in), a sharp pencil, and water.

Fill the bag about ¾ of the way full with water and seal it shut. Hold it up with one hand and use the other hand to firmly push the pointy end of the pencil through the side of the bag. Continue pushing it until the point is also coming out the other side of the bag. You might expect all the water to gush out over the floor, but believe or not, none of the liquid spills. This is because ziploc bags are made of a polymer. Polymers have long chains of molecules that are flexible. When you pierce a sharp pencil through the bag, the pencil slides in between the chain of molecules that make up the polymer.

The molecule chains make a seal around the pencil that won’t let the water out. If you want to be even more ambitious, you can push multiple pencils through the bag…just make sure you do it over a sink!