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(6) The term solubility, is applied to any thing capable

of being dissolved.

(7) Decomposition implies the separation of the elementary

substances of which any compo substance is formed.

(8) Volatilization is the art of rendering fixed bodies

volatile, or of melting them by fire into a fine thin vapour or spirit, which easily dissipates and

flies away:

(9) Sublimation is the condensing and collecting in a solid

form the fumes of bodies raised from them by heat. It differs but little from distillation, except that in the latter only the fluid parts of bodies are raised, but in this the solid and dry.

(10) Fusion is the reduction of solid bodies into a state

of fluidity by fire.

(11) If aqua regia be poured upon crude or raw antimony,

the metallic part will be dissolved, and the sulphur thrown out, in the form of a yellowish substance, partly to the sides and partly to the surface of the liquor; and this purified by sublimation appears the same with pure common sulphur or brimstone.

(12) Bitumens are certain bodies, which have a great re

semblance to resins and oils, and are found in sub

terraneous situations. It is considered that all Bitumens are of animal or vegetable origin ; and that the difference between them and resins, and other oily matters of vegetables and animals, are the natural effects of time, or of an alteration produced on them by mineral acids, or of both causes combined. Amber and jet (sometimes called black amber) are doubtless Bitumens, and the origin of jet is clearly traced. At Montpelier several cart-loads of trees have been dug up and converted into jet, with their original forms so perfectly preserved, that the species of trees thus bitumenised can often be determined. In Languedoc several pieces of wood are preserved whose external part is in the state of jet, while the internal part still remains in the ligneous state; so that the transition from the vegetable to the mineral state may be distinctly observed. The most singular instances, however, are those of a wooden pail and wooden shovel having been converted into jet, which is affirmed by undoubted authority.

(13) Calcination is the reducing of substances to a calx

by fire. Calx properly signifies lime, but it is also used for a fine powder remaining after the calcina.. tion or corrosion of metals and other mineral substances. It is a general fact that metals are always rendered heavier by calcination.

(14) Malleable is the capability of being spread by

beating

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(15) In many parts of France it is.customary to suspend a

bush outside any house where wine is to be sold 4. •' during the vintage, hence arises the proverb of

“Good wine needs no bush."

(16) Factitious is the being made by art, in opposition to

what is made by nature.

(17) Gen. chap. iv. ver. 22, “ And Zillah, she also bare

" Tubalcain, an instructor of every artificer in brass

and iron."

(18) Solid substances are reduced into powder by pul

verization, and trituration, or levigation. Pulverization signifies the separation of bodies into smaller ones, without destroying the elementary ingredients : brittle substances are pulverized by hammers. Trituration, or levigation, is the reduction of any substances to powder upon a stone with a muller, as colours are ground. Mechanical trituration, however carefully performed, is quite incapable of separating from each other substances that are chemically united.

(19) The polypi is an insect of a snail or jelly-like sub

stance, and possesses the wonderful property of each part becoming again a perfect insect, although divided into many pieces. It has been supposed by some naturalists, and is universally believed by the Negroes, that fish are rendered poisonous by feed

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ing on the coral polypi; but others have argued that the flat obtuse nose of fishes cannot possibly detach the polypi from their encasements. The numerous polypi inhabiting corals or corallines have always been found to protrude but little from their abode, which gives them a very peculiar appearance.

In some the animals are obvious, but in others they cannot be seen; but on passing the hand along the surface, the touch does not indicate the feeling of an immediately stony basis. Corals of recent formation are much more porous and fragile than when of some age; because the interstices have not been filled up, and those parts which have been formed require exposure to the air to consolidate and harden them.

(20) The Chinese have, within the last few years, suc

ceeded in cutting coral beads of much smaller dimensions than has been effected in Europe, which are called seed coral. Large balls of coral are sometimes worn among the Chinese as insignia of office; and there are extant many pieces of sculpture of this article; among them the finest specimen is considered to be a chess-board and men in the Tuilleries, Paris, which were the property of the late Queen of Naples. As it frequently occurs that corals are discoloured, the following method for cleansing them, and for removing any extraneous substance, may be serviceable:Steep them in a solution of potash and soft soap for a few days,

after which immerse them in warm water. If too much discoloured to render this effectual, steep them in a weak solution of muriatic acid, after which dip them in alkali, to neutralize the acid, and then wash them in warm water.

(21) Volatile, or odorous substances, seem particularly

destructive to the insects and animalcula that feed on the substance of the vegetables. The woods that contain aromatic oils are remarkable for their indestructability, and for their exemption from the attacks of insects, which is particularly the case with the cedar, rose-wood, and cypress.

(22) Metals which, though melted in the fire, do not

diminish in weight, or undergo any other sensible alteration, are called perfect metals, of which order are gold and silver. Those metals are called imperfect which are reducible by fire, and generally change into a calx; of this order are lead, copper, iron, and tin. The former of these possesses the property of changing into glass, and of vitrifying all the other metals except gold and silver. Quicksilver holds a kind of middle place, for like the imperfect metals it may be calcined, though not readily, and like the perfect ones it may be reduced by heat alone. The others are called semi-metals.

(23) Borax is a salt produced in the mountains of Thibet

in Asia, naturally, and artificially by evaporation.

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