Contractions. - Selen. Sel.

Selenium, Se.

A non-metallic element, very analogous to Sulphur in many of its chemical properties. It may be obtained from the operative chemists.

Characters and Tests. - A dull, lead-grey, amorphous substance, brilliant and brittle, yielding, when pulverized, a scarlet red powder without taste or smell. It fuses at a temperature a little above boiling water, and heated in the air, it burns with a blue flame, while part is volatilized in red fumes, emitting an odour like that of Bisulphide of Carbon. Insoluble in water, but forming a green solution in strong Sulphuric Acid, from which it is precipitated unchanged by dilution.

Preparation. - Trituration.

Reference to Horn. Proving. - Arch., xii.

Proper forms for dispensing. - lx to 3, Trituration only. 4, dilute Tincture only. 5 and upwards, Tincture, Pilules, or Globules.