It looks like actual magic – but it’s just science, as a tablespoonful of olive oil calms the waves on a huge area of a lake.
Dr Greg Kestin, a lecturer in physics at Harvard University showed off the trick this week on YouTube – but it’s a famous one.
Benjamin Franklin, one of the founding fathers of the U.S., used to carry oil with him – so that he could convince people he had the magic power to calm the waves.
In reality, it’s simple physics: the oil spreads into a layer one molecule thick, and prevents the wind from creating waves.
It’s because oil molecules are ‘double sided’ – with one part attracted to water, and another part repelled, so they spread into a thin layer.
Dr Kestin says, ‘Usually, the wind builds up waves by getting traction on the surface of the water.
‘But here, the oil acts like a tangled shaggy carpet on top of the water, which doesn’t bend or stretch easily, so instead of making waves, the wind just drags the carpet across the water.’