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"Invert the second vessel over the first, mouth to mouth, so that the contents of the two vessels shall be separated only by the paper. Each vessel is filled with an invisible gas. Remove the paper, and notice that the invisible gases quickly-diffuse into each other and form a dense cloud." -Avery 1895

Mixing Gases in Inverted Containers

"Invert the second vessel over the first, mouth to mouth, so that the contents of the two vessels shall…