498 



Mr. Lubbock on the Heat of Vapours 

 Table showing the constitution of the Atmosphere. 



According to this system of constants, the ascent for depressing 

 Fahrenheit's thermometer 1 is about 352 feet. 



* = -00028348 



= 9-5066765. 



If log a (in sex. sec.) = 1 '7669538 



log 



= ?' -^- = -74-514. 



i 



Seep. 473. 



= [9-5066765] Z7 2 + [9-8077064] U 3 + [9-8254352] U* 

 + [9-6827677] U 5 + [9-4289405] U 6 + [9-0902531] V 

 + [8-6829116] U s + [8-2178251] U 9 + [7-7028036] Z7" 

 + [7-1436673] J7 + [6-5450488] *7 12 + [5-9104758] C7 13 

 + [5-2429802] U 1 * + [4-5449962] Z7 1S + [3-8186763] Z7 16 + &c. 



F Xis found by changing U into X in the above series. Although 

 the development of co might be obtained by procuring the quan- 



titles 



d co 



d 2 co a P d co 

 -, &c., from , 



, 

 through the expressions 



given in p. 492. I have preferred employing the series 

 d(FX)* 



Q O) .55 1 r .A ^r . . 



dw dFX a d 2 (FX) s 





2 . 3 z 2 d X* 



a 2 d 8 (FX) 8 



+ &c. 



By involution from the expression for F X the following were ob- 

 tained : 



A 



= [7-3105250] X* + [7-9125849] X & + [8-2225672] ^6 

 + [8-3653575] X? + [8-3901249] ^ 8 + [8-3259417] Jf 9 



* I have adjusted the value of a so that the mean refraction at 45 might exactly 

 agree with that of M. Bessel. 



