Leonardo the hydraulic engineer: ‘Master of Water’

Water, the most dynamic of the elements, was a lifelong fascination for Leonardo. It revealed to him the principles of organisation and functioning of the natural world. Leonardo’s studies of water form a major focus in two of his notebooks, the Codexes Leicester and Arundel.

Leonardo’s studies of water in his notebooks formed part of his urge to understand in scientific terms the nature of what he was observing. He studied how spiralling waves carved out river beds, and classified how different shaped barriers controlled the direction of a current.

He measured and timed the flow of water, and explored how its percussive force shaped the courses of rivers. Leonardo then applied what he learnt to his work as a ‘Master of Water’ in Florence.

The diagram on the left is a detailed drawing of the flow of the Arno through the centre of Florence, includes measurements.

The long vertical lines indicate the banks of the river, while a series of horizontal lines represent four bridges.

The drawings accompanying this rather neat text in the Codex Arundel, are also part of the planned treatise on water.

They depict a collapsed wall in a flood, intersecting ripples in a narrow channel, and the spiral patterns created in the rocks of riverbeds by water erosion.

‘A new and effective breathing apparatus’

Here, Leonardo the inventor has drawn an underwater breathing apparatus. The part at the top holds two tubes for breathing in and out, and floats on the surface so seawater cannot infiltrate the tubes.

Leonardo says the device will enable a sailor to repair a hole in the side of a ship while at sea but he also foresaw its possible military use. In the early 16th century, a number of naval powers were competing for supremacy in the waters around the Italian peninsula.