During his time as a teacher at the Bauhaus, Paul Klee made an intense study of motion in the static, gravity-bound world and in that of the dynamic. The possibilities of movement open to birds and fish interested him particularly, as did their elements - air and water. Klee called water an »in-between realm«, in which the law of gravity does not apply and freedom of movement becomes possible. Kleeís collected works include more than sixty on the subject of fish, and about the same number of titles that contain the concept of water.