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CHAPTER XVIII 



d'Esserent in France, and has been described and studied experimentally 

 by Erclancher.18 He states that the first vessel of the multiple uses steam 

 at 223-7° F., or 3-9 lbs. gauge, and that it boils at atmospheric pressure. 

 The live steam used in the thermo-compressor is at 120 lbs. gauge, and i lb, 

 aspirates and compresses rather less than two lbs. of steam from the vapour 



Fig. 209 



space of the first effect. The single effect then will operate as a triple, and 

 in a triple each pound of live steam will operate at sextuple and each pound 

 of exhaust steam at quadruple effect. 



From experimental data, Erclancher has constructed the following table 

 here presented in Fahrenheit units : — 



Weight of Steam at Atmospheric Pressure aspirated and compressed to the 

 Stated Pressure by one lb. of Live Steam at the Stated Pressure. 



Pressure and temperature F° to which atmospheric 

 steam is raised. 



This system, though technically feasible, has not yet reached any great 

 extension. One objection to its use is that the temperature differences 

 available are necessarily restricted, and thereby very large heating surfaces 

 are implied. 



