PROOFS OF THE PROPERTIES OF MAGNESIA.

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Experiment III.

Magnesia attracts carbonic acid from the air.

If any quantity of magnesia be exposed to the air for sometime it soon attracts carbonic acid, which may be proved bypouring on it an acid, which causes a slight effervescence.

Experiment IV.

Carbonic acid has a stronger affinity for lime than for magnesia.

This may be evinced by digesting carbonate of magnesia infresh prepared lime-water. The lime will attract the carbonicacid from the magnesia and be rendered insoluble. Hence thetaste of lime-water is totally destroyed by carbonate of magnesia.

Experiment V.

Ignition of magnesia by the affusion of sulphuric or nitric acid.This experiment has been noticed already, vol. I. page 134.Experiment VI.

Magnesia combines with sulphur.

f

See vol. I. page 152.

The other properties of this earth require no experimentalinvestigation.