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 Rh of their preparation. The results of this double decomposition would be, the oxidation of the metal of the chloride, which in this new state would saturate, as the base of the chlorite, the acid employed; and a disengagement of gaseous chlorine would take place from a double source: from the chlorous acid and the metallic chloride.

Although this explanation may appear less natural than the other, it is nevertheless supported by analogous chemical facts. If, for example, a mixture of phosphuret of calcium and phosphate of lime be made red hot, phosphorus is evolved, and the residue is lime nearly pure; this for a long time favoured the supposition that this mixture was a phosphuret of oxide, whilst the contrary is now demonstrated.

The phænomena of oxidizement produced by the action of decolorizing compounds do not clear up the doubts which exist as to their true nature, for these phænomena may be explained by both hypotheses. Undoubtedly some are more readily so by one and some by the other, but there is no one to which they may not both be strictly applied.

We are, however, indebted to M. Liebig for some experiments which seem to render the hypothesis of the chlorites preferable. This able chemist observed that chlorine could not only expel carbonic acid from the bicarbonates, but also acetic acid, which is stronger, so as to form decolorizing compounds. Now it is difficult to conceive that a simple body can expel an acid from combination with a base; it is more natural to suppose that it is another acid, which overcomes the affinity even of the acetic acid; and this circumstance seems to justify the supposition of the existence of chlorous acid. It may seem astonishing, at first sight, that an acid so weak as chlorous acid, and which may be expelled from its combinations by carbonic acid, should, in its turn, expel acetic acid from its combinations. But the science presents us with facts equally singular, and which are well ascertained. Acetic acid itself, for example, decomposes the carbonates, and yet carbonic acid acting upon acetate of lead precipitates carbonate from it, and sets acetic acid free, which may be distilled.

Berzelius first undertook this subject, and among other interesting experiments, we are indebted to him for one, which, if it has not entirely settled the question, has at least thrown great light upon it. On passing a current of chlorine into a solution of carbonate of potash, saturated with chloride of potassium, this learned chemist observed, that from the first moment of the disengagement, the liquor became strongly decolorizing, and much pure chloride of potassium was deposited. The first action of the chlorine on the metallic oxide seemed to produce chloride of potassium. Then, as no chlorate was as yet deposited, and as in this experiment no deutoxide of hydrogen is formed, nor is any oxygen disengaged, it must be admitted that what is expelled from the metal by the chlorine has acted upon a portion of this elemenlary body, and formed with it some oxygenated compound, which is not