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ENGINE TESTS. 



Engine No. 46 is a cross-compound, with horizontal unjack- 

 eted cylinders and unjacketed receiver. The valves are all 

 plain slides. The steam was drawn from horizontal water-tube 

 boilers, and contained 0.7 % of moisture by calorimeter test. 

 The load was miscellaneous iron-working machinery. Tests 

 were made with two different loads. The valves and pistons 

 were all in excellent condition as regards leakage. 



It is evident from an analysis of the diagrams in these tests, 

 that the economy was as high as could be expected under the 

 conditions of boiler pressure, ratio of cylinder areas, and cut- 

 off. For higher economy a higher pressure, larger ratio of 

 cylinder area, and earlier cut-off are required. It must be 

 noted, however, that the distribution is not the most perfect, 

 and there is rather a high back pressure in the L. P. cylinder. 



