ENGINE No. 91. 



Diagrams 91& and 916 were taken from a 9" steam pipe 

 supplying a 28" x 48" Corliss non-condensing engine running 

 at a speed of 100 revolutions per minute. The pipe is a 

 branch from a long 12" pipe leading to the boilers, and its 

 length measured from the 12" is about 30 feet. The pipe 

 contains 6 short right-angle elbows. Diagram 91a is com- 

 plete for the entire revolution of the engine, and reveals the 

 pulsations produced by the admission at both ends of the 

 cylinder. Diagram 916 relates to one stroke. The indicator 

 diagram from the cylinder taken on the same stroke is also 

 shown. 



80- 

 60- 

 4O- 

 20- 



0- 

 8O- 



60- 



40- 



20- 







ENGINE No.Qla 



It will be seen that just before the beginning of the stroke 

 the pressure in the steam pipe drops ; and it is maintained nearly 

 constant until the cut-off takes place, when it immediately rises. 



325 



