176 ENGINE TESTS. 



consumption was found by weighing the water discharged by 

 the air-pump. Steam was drawn from the main service of a 

 large plant, and a calorimeter test showed that it was practically 

 dry. The main valve of the H. P. cylinder leaked quite badly. 

 The other valves and pistons leaked a small amount. The 

 engine supplied power to dynamos for electric lighting. A 

 series of tests was made with different loads, and in one case 

 the engine was run non-condensing. 



Considering the wide changes of load in the tests A, B, and 

 C, viz., from 295. H. P. to 123. H. P., the small difference in 

 economy, 15.71 to 17.22, is noteworthy. Probably the leakage 

 of the valves of the H. P. cylinder affected the matter, but to 

 what extent can only be conjectured. The economy is nt best 

 much below that obtained from some of the four-valve engines. 

 and excessive leakage is the only thing which satisfactorily 

 explains it. The results of tests D and E, condensing and 

 non-condensing, are respectively 16.07 Ibs. and 23.24 Ibs., from 

 which it appears that the consumption win MI running condens- 

 ing was 30.9% less than when running non-condensing. 



