r 126 ) 



temperatures. If in equation (1) we do not immediately introduce 

 v^ = b, we may write it as follows: 



I'l — b 

 b 



or 



F'or values of i\ ordy slightly greater flian b we may write 



i\ — h t\ 



for loa—. So we get: 



b ' b 



, p 27 7Y- v,—b 



pk ^ -i b 



Tiie value ot vai'ies with flie temnci'aturo ajid starts with 



the value zero for 7'=0^. It may be calculated from: 



-^ ii-—b) — RT. 



This last equation mav be written as follows : 



8 T [ b 



27 n 



't] 



T \Ö ^ v,—b 1 T 



With --=1— - we find for — ; — the value — and with >„ = 0,54 

 1 ic 02, b 5 1 /■ 



I . T 1 v^—b 



the value — -. With -;- = -- the value of — - — is equal to 0,2125. 

 4 i/k 2 b 



v,—b 27 T 



The quantitv Mxrving with the temperature, the term --- j— 



b ' b J/. 



does not represent the total variation of /? with the tempei'ature, 



T dp 



but the ditference is small. We might calculate the value of 



^ P clT 



from the above equation, but it is simpler to calculate this quantity 



from the following equation : 



