THERMAL PROPERTIES OF CARBONIC ACID AT LOW TEMPERATURES. 79 



EN TROP Y - TEMPERA TURE 



01 -05 



and therefore 



area P* idr\ , . , , 



j- I dp = 3<f> between pressure curves p l and p. f 

 "i "a Jpi \d6/f 



Similarly, if the area is bounded by the limit curve and the ordinate at j,, then 



area 



= S<f> between limit curve and pressure curve p t . 



corresponds in each case with the mean temperature 



