ENGINE No. 99. 



Diagram No. 99 was taken from a 6" pipe supplying a 14" 

 and 26" x. 42" compound engine running at a speed of 100 

 revolutions per minute. 



-40 



-120 



-100 

 -80 

 - 60 



40 



20 







The length of the pipe was 75 feet, and it contained two 

 short right-angle elbows. Here is another case where the lines 

 of the diagram are clearly marked, and there can be no miscon- 

 ception in regard to the action going on in the pipe. This dia- 

 gram is similar to the one which precedes it, and has the same 

 general features. There is this peculiarity, however, that there 

 is practically no drop of pressure during the period of admis- 

 sion. The drop occurs toward the very end of the previous 

 stroke. Subsequent to the cut-off and prior to this drop, the 

 pressure is well nigh constant. The indicator diagram here 

 given is from the head end, and refers simply to the high- 

 pressure cylinder. 



337 



