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Tills air it greedily re-absorbs from the atmo-sphere, and all other bodies with which it comeshi contact, and which can furnish it; hut itcannot unite with the air unless it is previouslymoistened. 100 parts quick-lime absorb about28 of water. It is soluble in about 700 partsof this fluid. To regain its full portion of airfrom the atmosphere, it requires a year or more,if not purposely spread out: it resists putrefac-tion; but with the assistance of moisture, itresolves organic substances into a mucus.

Marl is of three sorts; calcareous, argilla-ceous, and silicious or sandy. All are mixturesof mild calx (r. e. chalk) with clay, in such amanner as to fall to pieces by exposure to theatmosphere more or less readily.

Calcareous Marl is that which is most com-monly understood by the term Marl , withoutaddition. It is generally of a yellowish white,or yellowish grey colour; rarely brown or leadcoloured. It is seldom found on the surfaceof land, but commonly a few feet under it,and on the sides of hills, or rivers that flowthrough calcareous countries, or under turf inbogs. Frequently of a loose texture, some-