PROOFS OF THE PROPERTIES OF STRONTIA.

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When water is poured on sulphuret of strontia and thesolution is evaporated, hydro-sulphuret of strontia is obtained ina crystalline state, and a hydrogenated sulphuret of strontia re-mains in the solution.

Experiment III.

Strontia comlines ivith phosphorus.

(Phosphuret of Strontia.)

If six parts of strontia be mixed with one of phosphorus in aniron or earthern tube closed at one end, and the mixture be heat-ed gradually to a dull red-heat, a combination takes place accom-panied with a flash of light, as first noticed by Dr. Thompson.This phosphuret decomposes water, like the phosphuret of lime,discovered by Dr. Pearson.

Experiment IV.

Strontia comlines with oxigenated muriatic acid-, the decomposi-tion of which, ly sulphuric acid, is accompanied with a vividemission of light and increase of temperature.

This curious fact was first noticed by Messrs. Davy and Clay-field.* In order to form oxigenated muriate of strontia, let astream of oxigenated muriatic acid gas pass through a saturatedheated solution'of strontia in water, till it is neutralized, which maybe known by the solution having acquired an orange colour. Onpouring into this fluid a quantity of sulphuric acid, a great in-crease of temperature takes place, accompanied with a vivid emis-sion of light. But no light is developed, if the acid be pouredupon dry oxigenated muriate of strontia.

Q 3

West Country Coutrib. p. ill.