OXIGEN.

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SUBSTANCES NOT VET PRODUCIBLE BY ART, BUTANALOGICALLY CONSIDERED AS SIMPLE.

PART X.

SECT. I.

OXIGEN.

This substance although existing sometimes in a solid, andsometimes in an aeriform state, is never distinctly perceptibleto the human senses, but in combination.

We know it only in its combination, by its effects. Naturenever presents it solitary; chemists do not know how to insulateit. It is a principle which was long unknown. It is absorbableby combustible bodies, and converts them into acids. It is anindispensible condition of combustion, uniting itself always tobodies which burn, augmenting their weight, and changingtheir properties. It may be disengaged in the state of oxigengas, from burnt bodies, by a joint accumulation of caloricand light. It is highly necessary for the respiration of animals.It exists universally dispersed through nature and is a consti-tuent part of atmospheric air, of water, of acids, and of allbodies of the animal and vegetable kingdoms.

One of the most remarkable combinations into which it iscapable of entering, is that which it forms with light and caloric.The nature of that mysterious union has not been ascertained,but it is certain that in that state it constitutes the gazeous fluidcalled oxigen gas, which it will be more proper to considerhereafter.