Page:Cyclopaedia, Chambers - Supplement, Volume 1.djvu/504

 CHA

C H A

leaves this earth in every operation, and will to as long as it continues to be vitriol. Every time of the purification makes It indeed yield lefs and lefs ochre, but it feems as if it would always yield fome. Bafil Valentine pretends indeed that it will, after a vaft number of folutions, yield no more earth, and that then only it is fit for the feveral operations and won- derful experiments which he relates of it. But this is probably not true; and if it were, itfhould feem to prove no more, than that vitriol, when diverted of this earth, was a fubftance different from what it was before ; that is, that it ceafed to be vitriol, in the proper fenfe of that word. If the abfence of this earth could make this fait fit for purpofes, which in its natural ftate it was not fit for, it follows, that it muft be a very eflenrial part of its composition in that ftate.

Chalcanthum chkrum, in the materia medica, anamegiven by fome of the old Greek writers to the melanteria, a yellow- ish vitriolic mineral, which turned black on being wetted with common water.

CHALCEDONIUS, the name of a medicine defcribed by Ga- len, and directed by him to be infufed into the ears, in inve- terate difordersof that part. Cajl. Lex. invoc.

CHALCEDONY, [Cycl.) in natural hiftory, the name of a genus of the femi-pellucid gems, the characters of which are thefe : they are obfcurely-tranfparent ftones, of an even and regular, not tabulated ftructure, of a femi-opake cryftalHne bafis, and variegated with different colours, but thofe ever difperfed in form of mifts or clouds, and, if nicely examined, found to be owing to an admixture of various coloured earths, but imperfectly blended in the mate, and often viable in di- ftincr. molecula.

It has been doubted by fome, whether the antients were at all acquainted with the ftone we call chalcedony, they having de- fcribed a chalcedonian carbuncle and emerald, neither of which can at all agree with the characters of our rtone ; but we are to confider, that they have alfo defcribed a chalcedonian jafper, which feems to have been the very fame ftone, as they defcribe it by the word turbida, which extremely well agrees with our chalcedony.

There are four known fpecies of the chalcedony. i. A bluifh white one. This is the moft common of all, and is found in thefhapeof our flints and pebbles, in mafles of two or three inches or more in diameter : it is of a whitifh colour, with a faint cloud of blue diffufed all over it, but always in the great- eft degree near the furface. This is a little lefs hard than the oriental onyx. The oriental chalcedonies are the only ones of any value ; they are found in vaft abundance on the fhores of rivers in all parts of the Eaft-Indies, and frequently come over among the ballaft of the Eaft-India fhips. They are common in Silefia and Bohemia, and other parts of Europe alfo ; but with us are lefs hard, more opake, and of very little value. 2. Thefecond fpecies is the dull milky-vein'd chalcedony. This is a ftone of little value, and is fometimes met with among our lapidaries, who miftake it for a kind of nephritic ftone. It is of a fomewhat yellowifti white or cream colour, with a few milk-white veins. This is principally found in New Spain. 3. The third is a brownifh, black, dull and cloudy one, known to the antients by the name of the fmoaky jafper, or jafpis capnitis. This is the leaft beautiful ftone of all this clafs ; it is of a pale brownifli white, clouded all over with a blackifh mift, as the common chalcedony is with a blue. It is common both in the Eaft and Weft-Indies, and in Germany, but is very little valued, and feldom worked into any thing better than handles of knives. See the article Capnitis. 4. The fourth and laft fpecies is the yellow and red chalcedony. This is greatly fuperior to all the reft in beauty, and is in great repute in Italy, tho' very little known with us. It is naturally compofed of an admixture of red and yellow only,on a clouded cryftalHne bafis, but is fometimes found blended with the mat- ter of the common chalcedony, and then is mixt with blue: it is all overof the mifty hue of the common chalcedony. This is found only in the Eaft-Indies, and there not plentifully. The Italians make it into beads, and both they and the Germans call thefe cajfidonies \ but they are not determinate in the ufe of the word, but call beads of feveral of the agates by the fame name. i£7/'sHift. of Fofh" p. 465.

Chalcedony, in the glafs trade. See Gl a ss-chalcedony.

CHALCEMBOLON, x^*^^, in antiquity, afhip/thero- ftrum of which was of brafs.

The word is compounded of x a ^°h brafs, and Ef*/5oXov, ro- ftrum. Pitifc. Lex. Ant. in voc.

CHALGHUS, in ichthyology, a name given by the antient Greeks to the fifh which we call the doree. It feems to have obtained both thefe names from its colour ; the one from the word chalcos, brafs, and the other from doree, gilded, SeeFAEER.

CHALCIDICA lacerta, a fort of ferpent, fo called from its re-

femblance in colour to ihe chalcedony. Its bite is fucceeded

by a pellucid tumour, which has a kind of mining blacknefs at

the margin. Drank in wine, it cures its own bite, according

^ toPaulus ^gineta. It is alfo called feps. CaJ.Lex. in voc.

CHALCIDICUM, in antiquity, fometimes denoted a dining- room. SecCHALCIDIC, Cycl.

CHALCIS, in ichthyology, a name by which fome have called the pilchard ; called by others celerimis, and apua membras. Rondel, de Aquat. p. 85. Seethe article Pilch ardus.

Chalcis was alfo the name given by Ariftotle, ^Elian, Appian and the otherGreek writers, to the common herring. Sec the articleCLUPEA.

CHALCITAR1UM, in the materia medxa of the antients a name given by the Greeks of the middle ages to thecolcothar or calcanthum. t-ome have applied it to the chalcitis alone but others make it exprefs the vitriols in general. It is de- rived from the Arabian word colcothar, which is fometimes Written chabcuthar; from this to chalcitis is but a fmall change, and from chalcitis this word chaldtarium is formed by thefe writers, according to the cuftom of their times, of add- ing to words a termination, which feemed to make them di- minutives of the words they were formed o{, tho' no fuch thing was really meant, but it was merely the cuftom of the times. Thus they called the plant orchis, orchidium, and fo in numerous other inftances. Myrepftts, A'H'uts.

CHALCITIS, {Cycl.) in natural hiftory, filename of a foflile fubftance, very well known by name among the modern au- thors, but feeming to have been perfectly underftood but by- few of them. Many have accounted it a native pure red vi- triol, which is by no means the cafe ; and the generality have efteemed it one of the loft fulfils of the antients, tho* its name ftill ftands in the prefcription for the Venice treacle. This is, however, as erroneous an opinion as the other, the true chal- citis of the antients being yet exiftent, and in the Turkifn do- minions commonly known, and in frequent ufe as a medicine. It is a foft and friable fubftance, of a very irregular ftrudr.ure, and is eonfiderably heavy, and is found at different depths in the earth in loofe mafles of different fizes, from an ounce to two or three pounds in weight. It is ufually of a flatted fur- face, and undulated or clouded with various lines : it breaks with a fmall blow, and is then ufually feen to be compofrd of various feries of fhort, waved, and undulated ftria ; there are often five or fix feries of thefe in a piece of three quarters of an inch thick ; but other parts of the fame mafs are fometimes quite plain, and have no appearance of thefe ftriie. It is of a brownifh red colour, much refembling that of unpolifhed copper : if put into the fire, it burns firft to a dufky orano-e colour, and afterwards to a deep purple ; and if boiled in wa- ter, its faline part is diflblved, and may be afterwards feparated from the liquor, in form of cryftals of a greenifh vitriol, but of a faint tendency toward a rhomboidal figure, which is the fhape proper to thofe of the blue vitriol ; fo that this fubftance properly is a mixt ore of the cupreous and fcrrugineous vitriol. The Turks calcine it in a ftrong fire, and afterwards give it internally as a powerful aftringent, and, it is faid, with great fuccefs,

There is no doubt but that this is the very fubftance defcribed by the antient Greeks, under the name chalcitis ; the defcrip- tion of Diofcorides perfectly agreeing with, and very well ex- prefling it; he fays exprefsly, that chalcitis was of the colour of copper, friable, not ftony, and marked with fliining ftreaks or veins. He accounts it one of the more flightly corrofive medicines, and recommends the external ufe of it in colly- riums, and in haemorrhages, in an eryfipelas, and in the herpes. But the antients feem not to have known the ufe of it internally fo early as in thefe times ; tho' among the Ro- mans it was well known alfo in internal prefcription. and made an ingredient in the famous theriacaandromachi. Hill's Hift. of FolT. p 605.

Chalcitis, among the Arabians. The words chalcitis and colcothar, were of the fame bonification ; they exprefl'ed a vitriolic mineral, which Avifenna tells us was yellow. Jtwas a kind of what he calls alzigiat, or zagi, a word exprefling all the vitriolic minerals in general : the other forts of which were, the calcadis, which was white ; the calcanthum, which was green ; and the fory, which was red. Avifenna.

CHALCOL1BANON, a word mentioned in the apocalypfe of St. John, and very much mifunderftood by the intepreters, who generally render it brafs ; but the word will bear no fuch fignification. When the name of a metal is prefixed to fome other word, it only denotes the thing mentioned after the metal to be of the colour of that metal. This word is form- ed of the Greek chalcos, x a ** '> brafs, and olibanum, frankin- cenfe. We have many parallel compounds, and all under- ftood in the fame way, the name of the metal only expreflmg the thing to be of its colour : thus chryfomela are apples of the colour of gold, &c. This, therefore, can only fignify frank- incenfeof the colour of brafs, that is, yellow. Some in- terpret it to fignify a kind of brafs, which was dug out of Mount Lebanon in Syria ; but there are many reafons againft this : in the firft place, we do not find by any of the antients that there ever were any mines of copper in Mount Lebanon ; and, in the next, if this had been the fenfe to be exprefied, the word would not have been chalcolibanos, but libanochalcos. This all parallel compound words will evince ; and among the reft, the common compound of the name of this metal, ufed to fignify brafs, which being called mountain copper, was not exprefied bv the word chalcoreos, but oreochalcos, which by degrees foftened into orichalcum, and among the Romans into aurichalcum, a name erroneously fuppofed to have been formed of the word aurum, gold, and chalcos, cop- per. It is plain, however, that the Greeks meant nothing of gold by it, for they have mentioned a white orichalcum or

brafs,