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TEMPERATURE-ENTROPY TABLE. 



This table has been made to facilitate the solution of problems involv- 

 ing adiabatk action for steam and some other problems, 



It gives for each degree Fahrenheit and for each hundredth of a unit 

 ropy, the Duality, heat contents and specific volume, both for mote 

 and for superheated v i the pressures correspond- 



ing to the temperatures arc also giv< 



The pro|H-rtie> named may be more exactly stated as follows: 



t Steam 



Quality, A ; the jxirtion of a pound which is steam. 



it contents, AT -f q. 

 Specific volume, r - ATM + <r. 



Superheated Steam 



Quality, /-/,; the number of degrees of superheating. 



Heat contents, r + q + c f (t - /.,). 

 Spec it ic volume, v. 



arranged in groups of eight triple columns, four on each of 

 two pages, which face each other. Such a group is continued from the 

 highest to the lowest temperature; then comes the next group of eight 

 triple columns, etc. Commonly the solution of a given problem may 

 be found in a single group or in two successive groups. It is important 

 to note this feature of arrangement to avoid aimless search. 



For engineering purposes it will be found sufficient to take the nearest 

 tem|K.Tature of saturated steam and the nearest column of entropy, 

 and to take from the corresponding place in the table the required quan- 

 tities. At the highest temperature (420 F. ), the error of half a degree of 

 temperature corresponds to an error of a pound and a half in pressure; 

 the other properties have the following errors: heat contents 0.15 of a 

 "., and specific volume 0.008 of a cubic foot, which latter amounts 

 to half of one per cent. At lower temperature the variation of pressure 

 is progressively less, but the other two properties named are affected to 

 about the same degree. Such errors if they were carried into computa- 

 tions and united with other errors in such a way as to occasion greater 

 taintics would be liable to be inconvenient; but when found in the 



