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CARBONIC ACID GAS

CARBONIC ACID GAS,

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PART XIX.

SECT. I.

Carbonic acid gas is the first elastic aeriform fluid thatwas known. We find that the ancients were in some measureacquainted with it. Van Helmont called it the gas of Must, orof the vintage, or gas sylvestre.

We are indebted to Dr. Black of Edinburgh for the know-ledge of some of the most remarkable properties of this fluid.In the year 1755 he discovered the affinity between this gas andalcalies : and Bergman, in 1//2, proved that it was an acid.

PROPERTIES OF CARBONIC ACID GAS.

Carbonic acid gas is invisible. It extinguishes flame. It isfatal to animal life. It exerts powerful effects on living vege-tables. Its taste is pungent and acid. Its energy, as an acid,is but feeble, although distinct and certain. Neither light, orcaloric seem to produce any distinct effect upon it, except thatthe latter dilates it. It mixes without combining with oxigengas. It unites with water slowly. These two fluids, afterconsiderable agitation, at last combine, and form a sub-acid