SYSTEM NAPHTHALENE- CHLOROBENZENE-PHENOL, ETC. 



the fixed temperature was safely constant up to 0.01° durino- 

 the whole period of observation. The thermometer in the thermo- 

 stat was corrected by comparison with a thermometer standardised 

 at the Reichsanstalt. 



The electromotive force of the thermo-element was compensated 

 by a Weston standard cell of a very large capacity. The cell- 

 liquid contained no crystal of cadmium sulphate to eliminate 



temperature influence. 



Since the regular 

 compensation apparatus 

 was not at hand, we used 

 the ordinary resistance 

 box, and the mode of 

 compensation was as 

 shown in the diagram 

 (Fig. 3). 



A = standard cell. B = resistance box. 



C = thermo-element. U = mirror galvanometer. 



I) = commutator made of a paraffine block. 



Between a and ö 20000 ohms were inserted, while the neces- 

 sary resistance for compensating the thermo-electricity was put 

 between b and c. On closing d, e and /, </ we have the thermo- 

 electricity compensated by the fraction of the electromotive force 

 of the standard cell. On opening them and closing y, h we 

 have a circuit from which both the thermo-element and the 

 Weston cell are excluded, and we obtain the zero point of the 

 galvanometer, and even if very little thermo-electricity occurs, on 

 account of some inequality in the distribution of temperature in 

 the circuit, it may be thus eliminated by reading the zero point 



