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224. as the saturated solutions of carbonated soda; they were of a bright greenish yellow colour, and had an insupportable odour of chlorine.

5. The saturated solution (4) was then examined as to the change which had been occasioned by the action of the chlorine. It bleached powerfully, and apparently contained no carbonated alkali; but when a glass rod was dipped into it and dried in a warm current of air, the saline matter left, when applied to moistened turmeric paper, reddened it considerably at first, and then bleached it; and this piece of paper being dried and afterwards moistened upon the bleached part, gave indications of alkali to fresh turmeric paper.

6. A portion of the saturated solution (4) being warmed, instantly evolved chlorine gas, then assumed a dingy appearance, and ultimately became nearly colourless; after which it had an astringent and saline taste. Being evaporated to dryness at a very moderate temperature, it left a saline mass consisting of much common salt, a considerable quantity of chlorate of soda, and a trace of carbonate of soda. This mixture had no bleaching powers. The dingy appearance, assumed in the first instance, was found to be occasioned by a little manganese which had passed over into the solutions, notwithstanding the care taken in evolving and washing the gas.

7. From these experiments it was evident that when chlorine was passed in excess into a solution of carbonate of soda (3), the carbonic acid was expelled, and the soda acted upon as if it were caustic, a mixture of chloride of sodium and chlorate of soda being produced; with the exception of the small portion of carbonate of soda which, it appears, may remain for some time in the solution in contact with the excess of chlorine at common temperatures, without undergoing this change. The quantities of chloride of sodium and chlorate of soda were not ascertained, no doubt being entertained that they were in the well-known proportions which occur when caustic soda is used.

8. The Labarraque's soda liquor which had been prepared as described (2), was now examined relative to the part the chlorine played in it, or the change the alkali had undergone, and was soon found to be very different to that which has just been described, as indeed the experiments I had seen made