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STEAM ENGINES 



STEAM ENGINES 



INDICATING OF ENGINES 



Inside-Spring Indicator. The indicator is an instrument 

 that is used to determine the action of the steam in the cylin- 





FIG. 1 



der of an engine. A form of indicator having its spring inside 

 the barrel, or cylinder, is shown in Fig. 1. The instrument 

 consists essentially of a cylinder a containing a piston and a 



