Report of Judges on Stjsam Engines. 57 



EXHIBIT E. 



AmEKICAN IlSrSTITUTE EXUIBITIOJN', ) 



New York, Oct. 21^ 1S69. \ 

 Regulations Prescribed by the Judges, for the Practical Trials 

 OF THE Steam Engines Entered for Competition at this Exhibi- 

 Ticm. 



1. Experiments will be made to ascertain the relative economy 

 of the different engines. 



To accomplish this, each engine will in turn be selected to drive 

 the machinery in motion. 



The resistance will be kept as nearly uniform as possible and the 

 other engines be required to keep their clutch-pulleys in motion at 

 full speed to avoid friction. 



The power exerted will be ascertained by indicating ihe engine 

 and by dynamometers now in position on the shafting. 



Observations and diagrams will be taken every fifteen minutes, or 

 more frequently if the load varies greatly. 



The steam for the engine undergoing trial, will be supplied by the 

 Harrison boiler, which will be so arranged that'no steam is used from 

 it for any other purpose. 



The water supplied to and evaporated in that boiler will be 

 measured by means of a meter, and the coal burned may also be 

 weighed. 



Each engine will be required to drive the main shaft at 250 revo- 

 lutions. 



The speed of each engine is supposed to have been already 

 arranged by the exhibitor in ordering his pulley. 



The steam pressure shall be kept as nearly as possible at eighty 

 pounds above the atmosphere, to be measured in the steam-chest, 

 of the engine if desired. 



2. A trial will be made of the regulating apparatus of each engine 

 to ascertain the effect of suddenly changing the load or pressure. 



Trials will also be made to ascertain the difference in speed of each 

 engine when working regularly under different loads and steam pres- 

 sures. 



Also trials to determine through what range of steam ])ressure 

 each engine will run at regular speed ; the regulation', in all cases, to 

 be performed entirely by the governor with a wide throttle. 



The judges may also derange, if possible, the regulating apparatus 



