Crucibles, Por′celain

These beautiful ve els are now made in Germany and France of all shapes and sizes. They are formed of the most exquisitely white, thin, and hard porcelain, which does not crack when heated, and which is but little acted on by the most energetic chemical reagents. For some operations they supersede platinum crucibles, particularly in the ignition of the precipitates of the more reducible metals. They do not retain colouring matter, and are not porous. Their covers are excellently adapted for delicate cases of testing, the whitene of the porcelain showing the changes of colour in a single drop of liquid most distinctly.