Illustration showing an engine used to raise water. The weight of water in the lower bucket (A) pulls on the axle of the wheel at the top. This pulls the second bucket of water (B) upward until it empties into a trough (W) at the same time as the lower bucket empties into a drain (D). A gear lever then lets the buckets return to their original positions, at the level of the inflowing water (X). In practice, as with similar perpetual motion machines, the system does not account for the friction between components and therefore breaks the first law of thermodynamics. This engraving appeared in the Gentleman's Magazine of 1747.