( 292 ) 



For the critical condition r- must be 0. From this follows: 



\ovJt 



MET / db\_ a 



and after substitution of the values found for MRT and v 



db a if— I) 



dv f 



With f =4: and k = — it follows naturally that — = 0, whereas 

 "^ 3 ov 



15 

 with f =7 and x ^ -- it follows that: 



Ö6_45 

 "" öü~~49' 



In the same wav ( ^— ) must be in the critical state. From 



this follows 



d'b .^(/_l)(/-x)(/-4) 



— o — — :=: Ó 



Q 



With r'=4 and k := — this value is of course equal to 0. With 



15 ,.. , 



ƒ r= 7 and y- = -r ^^e find : 



3 



we fin 

 4 



d'b 

 -b — =0,1827 ^). 



(IT 

 Let us now proceed to calculate the value of 7—— at the begin- 



J ax 



ning of the plaitpoint line. We have the formula: 



ö'p ^ 1 f^i 



dT Uiv^xjT MRT \dxJ„T 



Tdx, d'6 



and have therefore to determine ( 4- I and ( --^ ) for the critical 



\uxJaT \oxdvjT 



condition, but on the supposition that b varies with the volume and that 



1) This high value of - h ^-^ supports the hypothesis that h, in its dependence 

 on the volume, lias a more intricate form than is represented by a series of ascending 

 powers ot 



