Summer heat, Carnot's engine and Archimedes

Today I felt grateful once again for Carnot (who indirectly invented all the heat engines - including the cooling air conditioners) and the Archimedes principle that explained us why/whether we float on a body of water.

Of course the floating would've been still there if Archimedes didn't discover buoyancy but for air conditioning I don't think we would know it - the history is the biggest evidence. That is why Carnot is my second most favorite scientist (first being Tesla). And the poor Sadi Carnot (yes, one of his names comes from the famous 13th century poet - Saadi Shirazi) died early of cholera in his thirties before getting noticed for his work.