HI. Rose on a new mode of preparing Aluminium. 171 
tallic oxyds only when the nascent potassium or sodium is at 
hand to combine with a part of the oxyd not yet reduced. Pure 
‘potash and soda, the properties of which are almost unknown 
tous, do not appear to form at that moment. And as alumina 
can very readily combine with alkalies to form an aluminate, 
it should be inferred, that the reduction of alumina through the 
alkaline metals might succeed in the end. 
But even if it should become possible to obtain aluminium 
directly from alumina, still cryolite may for a long time be em- 
ployed for the purpose, unless its price should rise immoderately. 
Nature furnishes this substance in a state of rare purity, the alu- 
minium is combined in it only with fluorine and sodium—two 
substances which cannot act injuriously during the production of 
the metal. Clay or aluminous earth is however seldom found in 
What in color as well as in lustre. They evidently were not as 
pure as the great majority of the globules, and probably contain 
some iron, 
A larger globule of aluminium of 3:8 grm. weight having 
been sawn in two, it could be plainly seen that the metal was 
brittle for about half a line from the outside ; but inside it was 
soft and pliable. Sometimes excavations are found in the inte- 
globules became in cooling radiated with crystals on its under 
surface, Déville believes he has obtained regular octahedral — 
i 
not appear to belong to the regular system. = yi 
_ Trying to melt x baper stole accidentally contaminated after 
being rolled without flux, before the heat rose so as to melt the 
Whole, small globules went floating on the surface. ‘The impure 
aluminium is less fusible than the pure which is mixed with it, 
expands in melting and rises out of the mass not yet fused. | 
‘8 @ phenomenon similar to that observed by Mr. Schneider with 
ismuth, 
iMpure bi: 
