Bell jar

Glass jar used in scientific experiments

A bell jar is a glass jar, similar in shape to a bell, and can be manufactured from a variety of materials. Bell jars are often used in laboratories to form and contain a vacuum. It is a common science apparatus used in experiments. Bell jars have a limited ability to create strong vacuums; vacuum chambers are available when higher performance is needed. They have been used to demonstrate the effect of vacuum on sound propagation.

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