I am looking for a brain Cubed Puzzle . Is a cube of glass(plastic) about 6cmX6cm , fullfill in water (liquid like water) . In the water there is a plasic object-like a boat 1cmX1cm (IN THE MIDDLE/CENTER OF THE CUBE). Somebody can not find what is it actually and why the plastic object is in the center and NOT in the top or botton or side... . If you play with it you will find that: there are two liquids in the cube and in the top of the cube null(not air, but nothing), the two liquids DO NOT reacted but are one on the other since other density have, the plastic object in on the top of liquid one(from floor) because of its density but on the botton of liquid two hence of density object-liquid2 , and there is the null on the event top , make more difficult to be found - what this cube contains ... ? I saw this trick/puzzle at a Psychiatrist Doctor Office ...