1324. Soot owes its efficacy to the ammoniacal salts it contains. The liquor produced by the distillation of coal contains carbonate and acetate of ammonia, and is a very good manure. The ammonia which it contains being partly in the free or caustic state; it must either be diluted with water, or saturated with some acid. This prevents it from destroying the plants manured with it, or being dissipated by evaporation. It may also be used with great advantage as an addition to composts or decaying vegetable matters of all kinds, as it assists in their decomposition, and reduces them rapidly to the condition of well-fermented muck.