on 18 February 2013
I was given this book as a present because I've always loved optical illusions. I looked through it and I thought it was just a load of pretty patterns. Then I took the trouble to read the introduction, which explains how to view autostereograms, and OMG! These things are amazing! It only takes a couple of minutes practice and then you feel your eyes 'lock on' and these incredible 3D images appear. Astonishing!