The compressor may be driven by a steam engine or in any other convenient manner.
The compressed air, leaving the compressor at the temperature T2, passes through the cooler, where it is cooled by means of water, and is then admitted to the expansion cylinder, where it is expanded to atmospheric pressure, performing work on the piston.
This is known as the membranous urethra, and is very narrow, being gripped by the compressor urethrae muscle.
The compressor draws in air from the room and compresses it, the work expended in compression being almost entirely converted into heat.
With dry compression, vapour alone is drawn into the compressor, and the temperature rises to as much as 180 or 200 degrees.