or Ambergrise, in natural history, is a solid, opaque, ash-coloured, fat, inflammable substance, variegated like marble, remarkably light, rugged and uneven in its surface, and has a fragrant odour when heated. It does not effervesc with acids; it melts freely over the fire, into a kind of yellow rosin; and is hardly soluble in spirit of wine.

Ambergrise is in general the most agreeable of the perfumes, and rarely accompanied with the inconveniences which other substances of this class frequently occasion. It is looked upon as an high cordial; and esteemed of great service in all disorders of the head, and in nervous complaints: a solution of it in spirit distilled from roses, stands recommended by Hoffman as one of the most efficacious corroborants of the nervous system. The Orientals entertain an high opinion of the aphrodisiac virtues of this concrete; and likewise suppose that the frequent use of it conduces to long life.

Ambergrise is found in great quantities in the Indian ocean, near the Molucca isles; as also near Africa; and sometimes near the northern parts of England, Scotland, and Norway. There have been many different hypotheses concerning its origin; but the most probable is that which supposes it to be a fossile bitumen, or naphtha, exuding out of the bowels of the earth, in a fluid form, and distilling into the sea, where it hardens and floats on the surface. See Chemistry, n° 513.