No; because part of this opening is needed to admit air into the vessel.
Why does the water flow freely, when there is an opening at the top as well as at the bottom of the vessel?
Because air is admitted at the top, and there is then nothing to obstruct the flow of water from the opening at the bottom.
What causes fruit, vegetables, and meat to spoil?
The air causes them to spoil.
How do we know this?
Because when kept from the air they remain good for a long time.
What is this process of keeping fruit called?
It is called canning.
How is fruit canned?