PHLOGISTON ſaturated with aerial acid.

Cronstedt Min. § 154. A. plumbago. Black-lead.

The true compoſition of this has been detected by Mr. Scheele.

§ 136.

PHLOGISTON united to the acid of vitriol and of molybdæna; or what amounts to the ſame, ſulphur joined to the acid of molybdæna.

Cronstedt Min. § 154. b. c. Molybdæna. Molybdæna.

The acid of molybdæna has never yet been obtained quite free from phlogiſton (§ 32). If this acid be of a metallic origin, molybdæna is a mineralized metallic ſubſtance, and ſhould be placed with the other minerals.

PETROLEUM.

§ 137.

Phlogiston occurs alſo in the foſſil kingdom, combined in an oily form; but many ſuppose this derived from the vegetable kingdom.