Abstract
The phenomena with relation to fluid mechanics are often taken up in scientific books for popular readers. However, the explanations on principle of them have been described under misunderstood knowledge on fluid mechanics in many books. It was said for a long time that siphons worked by the atmospheric pressure over an upper surface. But this model is wrong as many persons state. Also there are many ideas on the principle of a siphon. We discuss about the reason in this report.
