"like flames dying in Humphry Davy's bell-jar"

Bell jar and vacuum pump
Creative Commons AttributionBell jar and vacuum pump - Credit: Hannes Grobe
 Sir Humphry Davy (1778 - 1829), was an eminent English chemist and inventor. He is well known as the inventor of the Davy lamp, a safety lamp created for use in coal mines.

A bell-jar is a piece of laboratory equipment used in experiements to create a vacuum. A bell-shaped dome, often made of glass, is placed on a base, and then the air is sucked out using a vacuum pump. Davy would have used bell-jars in many of his experiments.