check this plz Hello my name is Hiroto Tanigwa. And today I would like to talk about Torricelli and his work finding the atmospheric pressure. It was known that well which depth is over 10 meters can not be pumped water directly. but people do not know why occur this phenomenon. Because there was not the concept of atmospheric pressure. In 1643, Torricelli experimented and proved the existence of atmospheric pressure. research question does atmospheric pressure exist ?