ci\i>rcTiviTV or s.ii.ii'M imi:oxiiK IN \oiT.ors SOLTTION. 309 



The values of ft and ft are deduced as follows. By differentiating the logarithmic 



equation we get 



1 dK n a . . 



K~rfT = r+T~;i 



where /t is the modulus 0'4343. 

 A second differentiation gives 



/0 . 



Putting d^K/flt* = 0, and substituting from (1) we get 



n a\* n 



n+\/n a 



and the points of inflexion are given by 



0, = ( n -v/n)-T, and ft = 



For the temperature of maximum molecular conductivity we put dK./dt = in (1), 

 and obtain for t the value t = fin/a T = (#i + ft) ; so that the temperature of 

 maximum conductivity is the mean between the two " tropical temperatures" 0\ and ft 



