THE ARTIFICIAL PRODUCTION OF DIAMOND. 
107 
Exi'ekiment. Result. 
Heated saniarskite, zircon, iron, carOorundnni, No. G grit, and lampblack Nil. 
Heated reduced iron, sand, and lampblack. Nil. 
Heated silicon and carbon. Nil. 
Heated olivine, sand, iron, and lampblack. Nil. 
Heated magnesia, sand, iron, and lampblack. Nil. 
Heated glass, sand, carljon, and iron. Nil. 
Heated ferro-silicon,-sand, carbon, and iron. Nil. 
Heated silicon, iron phosphide, iron, and carbon .. Nil. 
Heated silicon, manganese, carbon, and iron. Nil. 
Heated reduced iron, rouge, sand, and cai'bon. Nil. 
Heated reduced iron, sand, aluminium, and carbon. Nil. 
BULK PRESSURE AND VACUUM APPLIED TO A GRANULAR MASS. 
Experiment. Result. 
4-inch mould; 1-inch carbon rod with -|-inch iron rod down centre. Carborundum next to exit 
coarse carborundum round, the vacuum exit tube through side of tube and layer next iron 
mould protected by perforated steel plate and drawing the gases from turnings whitened, and 
the carborundum, iron turnings on top to bring current into rod, some crystalline plates. 
40 tons pressure, 72 k.w.m. vacuum 0'5 mm. absolute. 
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 oxalate and magnesium powder, heated 
dull red 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. 
PRESLilTfiD 
il SCEC.J9I9 
VOL. CCXX.-A. 
Q 
