505 



jipparatiis free of' tlieniio- electromotive forces by Diksski,hoh.st 's 

 method, supplied by 0. Wor.FF; tlie stretigtli of tlie current tlirongli 

 the resistances was 4 ni.a. For the delei'niination of (lie tempe- 

 ratures the vapour pressures of the lieliiim-bath were measured, 

 below 400 m.m. Hg. with the cathelometer ; the cori'espouding tem- 

 peratures were then derived by means of tlie formula of Comni. 

 N». J47/>, p. 33'). 



The results of 'tlie measuremenis follow in the tables I, 11, 111 and 

 IV. Near the vanishing-point, where the successive temperature 



TABLE I. Indium- 1922-1. 



') This formula lias been calculated out of measurements performed 1913. If 

 by the side of these measurements one takes those of 1911 into account, and 

 interpolates graphically, temperatures are obtained wliich often considerably deviate 

 fr(un those calculated with the formula. The vanishing-point temperature of 

 thallium e.g., graphically dei'ived in this way in Comm. No. ]6Üa, is 2°'ó2 K; 

 the formula gives 2,°47 K. Until the vapour pressure curve of helium is more 

 accurately known, we give the read vapour tensions, and state also, how we have 

 calculated the temperatures h-om them. 



^^ Below the vanishing-point the measured potential differences have been re- 

 calculated to resistances, as if Ohm's law were valid. 



