If the cube is only partially immersed in the fluid at a depth of **h**, the submerged volume **v** is **h x H**^{2}. The side thrusts on the vertical opposite sides again cancel each other while the upward buoyant force is **ρgh x H**^{2} = ρgv, i.e. weight of the fluid displaced by the submerged portion of the cube. If the cube stays floating in the fluid, the buoyant force must be equal to the weight of the cube (neglecting the effect of the fluid surface tension). By the same token, **a vessel floating in water displaces an amount of water equal to its own weight**.

Thanks to the Archimedes’ Principle, an ingenious and green design is made possible for a rotating boat lift in Scotland linking two canals with a level difference of 35 metres.