THE ARTIFICIAL PRODUCTION OF DIAMOND. 



107 



EXPERIMENT. 



Heated sainarskite, zircQti, iron, carborundum, No. 6 grit, and lampblack 



Heated reduced iron, sand, and lampblack 



Heated silicon and carbon 



Heated olivine, sand, iron, and lampblack 



Heated magnesia, sand, iron, and lampblack 



Heated glass, sand, carbon, and iron 



Heated ferro-silicon, sand, carbon, and iron 



Heated silicon, iron phosphide, iron, and carbon 



Heated silicon, manganese, carbon, and iron 



Heated reduced iron, rouge, sand, and carbon 



Heated reduced iron, sand, aluminium, and carbon 



RESULT. 



Nil. 

 Nil. 

 Nil. 

 Nil. 

 Nil. 

 Nil. 

 Nil. 

 Nil. 

 Nil. 

 Nil. 

 Nil. 



BULK PRESSURE AND VACUUM APPLIED TO A URANULAR MASS. 



EXPERIMENT. 



4-inch mould; 1-inch carbon rod with J-inch iron rod down centre, 

 coarse carborundum round, the vacuum exit tube through side of 

 mould protected by perforated steel plate and drawing the gases from 

 the carborundum, iron turnings on top to bring current into rod, 

 40 tons pressure, 72 k.w.m. vacuum 0'5 mm. absolute. 



RESULT. 



Carborundum next to exit 

 tube and layer next iron 

 turnings whitened, and 

 some crystalline plates. 



SEALED TUBE EXPERIMENTS. 



EXPERIMENT. 



Heated sodium, calcium carbide and water in sealed iron tube at 400 C. 

 Heated sodium carbonate and carborundum in sealed iron tube to red 



heat for 50 minutes, sodium silicate and amorphous carbon formed. 

 As above, but heated for 2 hours 10 minutes at an orange heat, not 



so much carbon and silicate formed as in previous experiment. 

 Sealed tube containing ferrous oxalatc and magnesium powder, heated 



dull red i hour. 

 Sealed tube half filled with olivine, graphite, sugar and water, heated to 



full red for 1 hour. 



RESULT. 

 Nil. 

 Nil. 



Nil. 



Amorphous carbon. 

 Nil. 



VOL. OOXX. A. 



