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"After thorough drying, the air to be liquefied enters through the pipe a, and in the compresor C is compressed to about 200 atmospheres. R is a water cooler, to remove the heat of compression. The air thus cooled and strongly compressed passes down through the inner tube of the helical coil H to a valve below." —Derr, 1911

Air Liquefaction Machine

"After thorough drying, the air to be liquefied enters through the pipe a, and in the compresor C is…