The Ericsson engine, invented by Swedish-American inventor John Ericsson in 1833, is based on a cycle that  esembles a Stirling cycle except that the isometric steps are replaced by isobaric steps. It uses a re generator in the same way as a Stirling engine. Sketch the Ericsson cycle in the pV- and ST-planes. What is the efficiency of an ideal, reversible Ericsson engine?