2 PROPERTIES OF STEAM AND OTHER VAPORS. 



Pressure of Saturated Steam. As a conclusion from all the experiments 

 on the tension of saturated steam, Regnault * gives the following data : - 



From these data he calculated, by the aid of seven-place logarithms, 

 the following formulae, which give the pressure in millimetres of mercury 

 for any temperature in degrees Centigrade: 



A. For steam from -- 32 to o C, 



p = a + ba n . 



a = 0.08038. 

 log b = 9.6024724 10. 

 log a = 0.033398. 



n = 32 - /. 



B. For steam from o to 100 C, 

 log p = a - ba n + cfi n . 



a = 4.7384380. 

 log b 0.6116485. 

 logc - 8.1340339 - 10. 

 log a - 9.9967249 - 10. 

 log ft - 0.006865036. 

 n = /. 



* \ffmoires de V Insitut de France, etc., tome xxl 



