93 



W represents a water itmnp, wliile J3 and C are filter flasks. 

 F represents a clip, S a rubber stopper through which the tube 

 PLH passes. 



is left open at M. A manganin wire iVjiVj serves as a Iieaier ; 

 5 or 6 storage cells are used as a source of current, whilst a 

 regulating resistance and an ammeter are put in the circuit. 



The purpose of the wire xViiV, is to heat that part of PLH 

 which is not heated by the oil bath, above the melting temperature 

 of sodium in order to prevent the solidification of the molten metal 

 when flowing from lo G. The wire is separated from the wall 

 of the tube by means of asbestos paper. In order to prevent loss of 

 heat the wire is also covered with asbestos paper. Tlie oil bath is 

 heated to 130" and when the metal has entirely melted the stop- 

 cock E is shut, the heating current started, and the pump W put 

 in action As soon as the tube M is sufficiently heated the clip F 

 is cautiously opened. The molten metal flows into the dilatometer 

 and displaces the rock oil present which flows into the flask 6'. 



As soon as the sodium reaches F (the dilatometer being then full 

 of the metal) it solidifies, as the side tube is at room temperature. 

 In this way suction stops automatically '). The stopper S is now 

 removed while the tube J'LH is taken out of the dilatometer. The 

 level of the metal falls and the rock oil present protects the sodium 

 from oxidation. 



After the solidification of the metal which is accompanied by a 



') If any molten metal slioukl still pass over, it enters the flask C containing 

 some rorlc oil which covers llie metal. 



