Hole in Your Hand Experiment

Here's a cool science experiment you can do with your kids that makes it appear as if there is a hole in your hand.  It's more of an illusion than a science experiment, but cool nonetheless.  I learned of this illusion watching a short video produced by the BrainCraft team on YouTube.

One Weird Visual Illusion Explained

Begin by taking a regular sheet of white printer paper.  Any color will do.  Roll it into a long, narrow tube, about the size of a quarter.  Make sure both ends remain open so you can see through both ends as shown below.

Look through the tube with one eye.  While keeping both eyes open, bring the palm of your hand close to your other eye, an inch or two away.  Slowly bring the palm parallel across your eyes until it touches the tube of paper.  As you do this, you should see a hole appear in your hand!  Obviously there is no hole in your hand but a cool little illusion trick nonetheless!  

Why is this happening?  I'll point you to the video link above for details.  BrainCraft does a much better job explaining than I ever could!