84 
TP{E IION. SIR CHARLES ALGERNON PARSONS; EXPERIMENTS ON 
It was thought that the vapour from boiling iron saturated with carbon might, by 
the action of bisulphide of carbon, cause a crystalline deposit, but all the experiments 
to this end yielded no results. 
Ex'periments under X-ray Vacuum. 
Experiments were made under X-ray vacuum in a new chamber of cast iron with 
very thick walls to absorb the heat, exhausted through an 8-inch diameter suction 
liy a large molecular pump alongside, in series with a dry, high speed, two stage, 
pump, 12-inch diameter pistons, and last of the series a 3-inch + 2-inch compound 
Fig. 12. 
Fleuss. The crucible was resistance-heated as before (fig. 12). No diamond was 
produced in any of these experiments, except in those where iron, sand, and other 
elements, with or without sulphur, were first heated and well boiled in the carbon 
crucible at atmospheric pressure, and after cooling transferred to the vacuum furnace 
and re-heated by resistance under X-ray vacuum; violent ebullition occurred owing 
to the liberation of occluded gases, and many iron spherules were ejected, which 
cooled by radiation and conduction where they fell; diamond was found in these, 
which burnt in oxygen, but no diamond was ever found in the ingot remaining in the 
crucible. 
