(see Chemistry, p. 178, &c., in this Suppl.) when well fused, is, according to Guyton d'Arce Morveau, of no higher specific gravity than 8.3466. This is very different from the specific gravity which has hitherto been assigned to it. The same eminent chemist concludes, from its extreme brittleness and difficulty of fusion, that it affords little promise of utility in the arts, except in metallic alloys, or by virtue of the property which its oxid possesses, of affording fixed colours, or giving fixity to the colours of vegetables.