ENGINE No. 67. 



Single valve, 8" x 10": Speed, 326 revolutions per minute. 



This engine is of the automatic cut-off type with shaft gov- 

 ernor, shifting eccentric, and balanced slide valve. These 

 diagrams show the effect of unequal adjustment of the lap of 

 the valve. The first set, Q7a and 676, was taken with the 

 engine loaded. The mean effective pressure at the head end 

 is 8 Ibs., and at the crank end, 32.4 Ibs. The second set, lc 

 and 67cZ, was taken with a friction load. Here the mean effec- 

 tive pressure at the head end is a minus quantity, and at the 

 crank end a plus quantity. The third set, 670 and 67/, was 

 taken under the same conditions of load as the second, after 

 equalizing the lap. With this adjustment the mean effective 

 pressure at the head end was 1.9 Ibs., and at the crank end, 

 3.4 Ibs. 



ENGINE No. 67a 



Head End 



r-30 



20 

 10 

 



ENGINE No. 67b 



Crank End 



-60 

 -50 

 -40 

 -30 

 -20 

 -10 

 - 



287 



