The Original Book of the Mind by Peter Warlock and Tannens

A incredible book test from Peter Warlock using a innocent looking slate that holds all the “keys”.  When you need them they are there.  When you don’t the slate is so cleverly gimmicked that you would never expect it as anything but innocent.  Comes with the original books. The slate is capable of being redone with your own books if you wish.  Circa 1960’s.  Hard to find this one!

I wish i could photograph the workings for you  (its that cool!) but this was later produced by Viking and others so I have chosen not too.