rct.uk

pYN6p TIL king James I of England had a samurai armor
4Xdm5 TIL That Leonardo Da Vinci once conducted an experiment to understand the flow of blood through the valves of the heart, by pouring hot wax into one, making a mould of thin glass from the cast, and then pumping water mixed with seeds through it. He saw how a heart actually regulates itself.