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The so-called siphon principle.
It's a principle of physics.
The essence of the siphon effect is due to the pressure of the liquid and atmospheric pressure.
And in clinical surgery, there is an interesting story that goes something like this.
For example, the normal blood pressure in the human body is 110 millimeters of mercury.
Whereas atmospheric pressure clearly amounts to 730 millimeters of mercury.
Why then does blood choose to flow out rather than back into the body when the blood vessels rupture?
In fact, this is a misconception.
Because atmospheric pressure is an absolute value.
But blood pressure is not so, as it is the pressure of the blood against the walls of the blood vessels.
Therefore, the actual absolute pressure of blood pressure is: the measured value + atmospheric pressure.
This phenomenon occurs from time to time in clinical surgery, but is exceedingly rare.
