Hare's Blowpipe. 291 
Crark. Pure Oxide of Magnesium (Magnesia.) 
- Fusion per se, extremely difficult. When the earth is 
made to adhere (by moisture with distilled water and sub- 
sequent desiccation) and placed upon charcoal it is fusible in- 
toa whitish glass ; but the parts in contact with the char- 
coal acquire an imposing pseudo metallic lustre with a pur- 
ple coloured flame. 
Cuarx. Hydrate of Magnesia (pure foliated Magnesia 
from America.) 
“This substance is incomparably refractory ; with the 
utmost intensity of the heat of the gas blowpipe, it is ulti- 
mately reducible to a white opake enamel invested with a 
thin superficies of limpid glass. Its fusion is accompanied 
with a purple coloured flame. 
Experiments on Corundum. 
Silliman, page 112. “Corundum of the East-Indies 
Was immedia ly and perfectly fused into a grey globule.” 
* Corundum ° ina the s ith active ebullition.” 
hute cavities caused by the escape of gas during its fusion. 
This gas is probably the same which pure silica more 
abundantly exhibits. A slightly coloured greenish flame 
accompanics the fusion of corundum.” 
Experiments on Sappar. 
Silliman. Sappar or kyanite perfectly and instantly 
fused with ebullition into a white enamel.” | 
ed (when both substances had become cold.) This enabled me to make it 
receive the greatest heat of the flame on renewing the process. The lime 
then melted into a liquid, which subsiding round the globule of platina, 
"used it to appear after cooling as ifset in enamel. 
