NATURAL HISTORY OF ALUMINE.

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ALUMINE.

PART LIX.

SECT. I.

NATURAL HISTORY OF ALUMINE.

i HIS earth derives its name from alum, of which it forms thebase. It constitutes the lower strata of mountains and plains.It arrests the waters and causes them to rise in springs to thesurface of the earth. It enters into the natural composition ofthe schistus, and all those stones and earths called argillaceous,such as potter s-clay, fuller s-earth, lepidolite, mica, corundum,is’c. Hitherto it has not been found pure any where, exceptin the garden of the public schools at Halle in Germany.

PROPERTIES OF ALUMINE.

Alumine is white, and soft to the touch. It is insipid, ad-heres to the tongue, and occasions a sense of dryness in themouth. When moistened with a small quantity of water itforms a tenacious, ductile, kneadable paste. When heated toredness it shrinks considerably in bulk, and at last becomes sohard as to strike fire with flint. After being ignited it is nolonger capable of being kneaded with water into a ductile mass.It recovers however this property by solution in an acid and pre-cipitation. Alcalies dissolve it in the humid way, and form com-

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