This Cartesian diver game is guaranteed to get anyone hooked on science! The soda bottle houses two divers: a hook and a sinker. The hook diver has a wire attached that is bent in the shape of a hook just big enough to latch onto the loop of wire extending over the top of the sinker diver. The sinker rests at the bottom of the bottle while the hook diver floats. The object of the game is to make the hook diver sink by squeezing the soda bottle and to hook the sinker on the bottom. It's a game of science and skill and lots of fun frustration