Forking hell :-)

[Jonopen]

Apologies for the slightly attention grabbing title!

Yes, it an unusual illusion, obviously not of my invention. I believe it goes back to the 1960’s.

I have an ongoing personal project to draw a few more optical illusions. Here another one I did a while back. It’s a copy of an impossible object originally created by the Swedish graphic artist Oscar Reutersvärd (1915 - 2002).