Optical Illusions

Sorry, don't get excited by the title. It's rather disappointing. As the title suggests, I would like to post some optical illusions from a book I just borrowed from the library. I adore optical illusions (they're like puzzles where you don't have to use your brains so much) and apparently so does Mrs. Koh. It has illusions such as length distortions, afterimages and how to make 2-D objects into 3-D! Yes, all you need to do is follow the instructions and use your eyes!

Sadly, it appears I would be infringing copyright. :(

Never mind, at least you can still borrow the book from the library. It's called "Can you believe your eyes?: Over 250 illusions and other visual oddities" by J.R. Block and Harold E. Yuker. It's a thick red book which you've probably seen me reading recently. I found it at the Maths Sphere! Strange...

:)
Glen

P.S. No, I did not get my puzzles from this book, in case you were wondering.