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1818.] blackened by exposure to light, though without liberating any gas. Thrown into water the ammonia was separated, forming a solution, and the chloride remained unchanged. Heated, the whole of the ammonia was given off. Placed in chlorine it inflamed spontaneously, and the ammonia was decomposed.

Chloride of silver that had been well dried, but not fused, gave the same compounds with ammonia, but in a much shorter time.

A strong solution of chloride of silver in ammonia was left for some weeks in a bottle stopped only by a piece of paper. At the end of that time several perfectly colourless and transparent crystals had formed in it; some of them being as much as a quarter of an inch in width. Their general form was that of a flat rhomboid, but sometimes two acute angles of the rhomboid were wanting, and then the crystals looked like hexahedral prisms with oblique bases.

Exposed to the air, these crystals became opake, gradually losing the whole of the ammonia, and were then so friable as to fall into powder by a slight touch; the substance remaining was a dry chloride of silver. Placed in water, the same change occurred, but more readily; the water separated the ammonia, and they instantly became opake. Heated, they gave off much ammoniacal gas, and the chloride remained unaltered. Exposed to light, they gradually blackened, though covered by the solution from which they were deposited.

If the ammoniacal solution be weak, other crystals are formed which are pure chloride of silver.

Dry corrosive sublimate placed in ammoniacal gas had suffered no change in fourteen days, nor had any action been exerted on the ammonia; there was a diminution of a quarter of a cubical inch of gas, probably owing to a little water being present. The corrosive sublimate heated gave out no ammonia, and the whole of the gas remaining was absorbed by water.

The precipitate obtained by adding ammonia to a solution of corrosive sublimate appears to be a compound of the two bodies, but the alkali is neutralized in this case, and it is therefore more analogous to the combination of ammonia with the chloride of tin. When the precipitate is distilled, it gives off ammoniacal gas and also some azote, and the corrosive