496 Mr. Lubbock on the Heat of Vapours 



u = u" — U. See p. 490. 





»= 1 



H* 





H, therefore 



y— 1 



If we take, as in p. 274, y — 1*5, 



f» = 1 - -^r^c"*- 1 + #} p = p> (I- 



Seep.280, 0=l'«f I + 0' lZ _1 



F U J £ * 



co= 1 



A:(l+a0') 



-#. 



See vol. xvi., p. 440. 



agH/3 



y-l 



Ep y 



Zzi "" 

 i — Ep y 



In page 470 I found H= '54378 (from the observations of M. 

 Gay Lussac) corresponding to the temperature 87 ,0 35 of Fahren- 

 heit, and to 30*145 inches of mercury in the barometer. As the 

 uncertainty with respect to the values of y and E appertaining to 

 the mean state of the atmosphere makes it useless to have recourse to 

 greater refinement, I shall now suppose that this value of if will be 

 sufficiently exact for the temperature 50° of Fahrenheit and for 30 

 inches of mercury in the barometer at the earth's surface ; the sequel 

 will show that this hypothesis is admissible, and the calculation of 

 i will stand thus: when y = 1*5 



k 

 losr — — r = 4*2633392 log/3 = 9*5223787 



gM 



logM = 9*6377843 

 log (1 + *!') = 0*0159881 



3*9171116 

 6*0624187 



log H = 9*7354232 

 a = 6*8041168 



6*0624187 



log i = 7*8546929 



i = -0071564 



,*' — 



=5 Nap. log yz~h ~ '78478, 



