One of the first known experiments on how combustion needs air was carried out by Greek Philo of Byzantium in the 2nd century BC. He wrote in his work "Pneumatica" that turning a vessel upside down over a burning candle and putting water around this vessel meant that some water went into the vessel. Philo thought this was because the air was turned into the classical element fire. This is wrong. A long time after, Leonardo da Vinci worked out that some air was used up during combustion, and this forced water into the vessel.