70 
THE HON. SIE 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 Carhon under Pressure hy 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. Richaed Threlpall 
Aehestos 
k mica 
liner 
Presspahn 
insulation 
: —Magnesia 
Magnesite 
RuhRer 
~~ cup 
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 
