70 THE HON. SIR CHARLES ALGERNON PARSONS : EXPERIMENTS ON 



experiments, however, indicates in most cases an association with iron, whether 

 introduced intentionally, or present from the melting of the poles, or from other 

 causes ; allusion to this is made in the Appendix. 



Experiments Designed to Melt Carbon under Pressure by Resistance Heating. 

 In the attempts to melt carbon under pressure by this method (fig. 3) heat was 

 applied for a duration of 5 seconds, sufficient in amount to melt the graphite core 

 six times over, with the result of only altering the structure. RICHARD THRELFALL 



Asbestos 



& mica 



liner 



Presspalm 

 insulation* 



Magnesia 



Magnesite 



RuTober 



packing 



Fig. 3. 



independently came to the conclusion from his experiments at about the same time, 

 1907, that under 100 tons per square inch, graphite, electrically heated, remained 

 graphite. 



It appeared, however, desirable further to investigate the possibility of carbon 

 losing its electrical conductivity when approaching its melting point, as alleged by 

 LUDWIG and others, and of thus shunting the current from itself on to the contiguous 

 molten layers of the insulating barrier surrounding it. There had, however, been no 

 indication of this having occurred, even momentarily ; the evidence was rather that 

 the graphite core had been vaporized and condensed in the surrounding parts of the 



