ENGINE No. 73. 



Four valve, 26" x48". Speed, 50 revolutions per minute. 



The steam valves in this engine are slide valves, and the 

 exhaust are Corliss valves. 



The change here consisted in moving the driving-gear for 

 the steam valves one tooth ahead, the total number being 42, 

 and in shortening the exhaust rod so as to reduce the lap on 

 the exhaust valve. The diagrams were taken from the head 

 end, No. 73# before, and No. 736 after, the changes. 



ENGINE No. 73a 



ENGINE No. 73b 



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