“Never assume that Leonardo Da Vinci’s doodles are meaningless. A page of Leonardo’s scribbled notes from 1493—previously dismissed as “irrelevant” by art historians—is actually the first written demonstration of the laws of friction.
‘The sketches and text show Leonardo understood the fundamentals of friction in 1493,’ Hutchings said in a statement. ‘He knew that the force of friction acting between two sliding surfaces is proportional to the load pressing the surfaces together and that friction is independent of the apparent area of contact between the two surfaces. These are the ‘laws of friction’ that we nowadays usually credit to a French scientist, Guillaume Amontons, working two hundred years later.'”