Page:Cyclopaedia, Chambers - Supplement, Volume 1.djvu/421

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CAD

ore, it is eafily tried by- fire ; for the glafs producible from thefe feveral things, fo like in external appearance, is wholly diffe- rent. The glafs from the white pyrites is black, that from the grey copper ore is red, and that from the filver blackifh ; but that from the cobalt is of the fine blue of which we make fmalt. This is an exact fapphire colour, and probably from this colour obtained the name of zaffer, which is at prefent generally ufed tofigntfy roafted cobalt, which is blue, and becomes of a ftrong harclnefs on lying by a little wetted; but fome ufe it in gene- ral, either for this, or for the fmalt prepared of it. Cobalt, whenexpofedforaconfiderabletime by itfelf in aheap to the fun andrain,yieldsan efflorefcence of a rofe or peach bloflbm colour, called by the miners the flower of cobalt, and very much refemblinK the native flowers of cobalt described before, but lefc beautiful : this efflorefcence when properly treated affords a very fine red colour for the painter's ufe, and a little green vitriol Spirit of nitre difiblves the cobalt with a violent effer- vefcence ; four times the quantity of the acid is fufHcient to dif- folve fome cobalt, but other ores require fix times or more:

' this is owing to the purity or impurity of the ore. The folution is of an uncertain colour, according to the other matters con- tained in the cobalt ; when it contains vitriol it is blue, when it contains copper, as is often the cafe, but particularly in that kind called by the miners copper nickle, which has an appear- ance of copper on the furface, the folution is then green ; it is alfo fometimes green from the pureft ores to appearance. This green colour refembles very much that of fait of fteel well pu- rified, but it ftillfeems to have fome ihare of copper in it. When the folution is redifh, it mews that there is a mixture of bifmuth ore in the cobalt; and finally, when it is ycllowiih, it {hews the edbalt to be richeft of all for the making of fmalt. The folutions of cobalt, when an alkali is added, fuch as oil of tartar, or the like, precipitate a fine blue fmalt, winch is the richeft of all colours for china ware : it is poffible that this was | the old blue employed by the Chinefe, which we find fo greatly | fuperior to that ufed at prefent, but our fmalt being afforded fo much cheaper than they could make this elegant colour, they , foon difufed it, and made their blues wholly from our fmalt. : Oil of vitriol, and fpiritof fea fait, acton cobalt, but do not pro- , perly diffolve it : they may rather be faid to erode it, and par- ■ ticularly the acid of vitriol, which turns it into a white pow- der, fo that fpirit of nitre feems the proper fimple folvent of it. Pkilof. Tranf. N° 396. p. 199.

Cobalt put into a coated retort, and fct over a ftrong fire, yields thick fumes, which by degrees afiemble themfelves in the neck, and upper part of the veflcl, in form of a folid fubftance. This is white arfenick, or ratfbane, but the ore is feldom fo pure as to yeild thefe flowers white and perfect from the beginning ; they are often blackifh at firft, and after this red, which fhews that there is fome portion of common fulphur in the cobalt, which mixing with the arfenick, turns it red, as it will com- mon white arfenick, efpecially if a little fcorice of copper be ad- ded, or in the firft cafe if a little copper be contained in the cobalt.

Thefe red flowers form themfelves into a folid fubftance of a laminated ftrm&ure, and have much the appearance of a regulus of fome kind, but they alter on being expofed to the air, and though very bright and glofly at firft, they become opake and dull afterwards. When roafted, as the miners term it, in a reverberatory oven, in which the flame of the wood is beat back upon the ore, ityields a white dufty fubftance like meal, which flicks to the top of the oven, and is collected for the making of the common white arfenick, and the other kinds. The re maining fubftance, after all thefe whiteflowcrs are raifed, is on \y the fixed earth which turns into that blue glafs called fmalt. Bifmuth ores, treated in the fame manner, yield their metal for the common ufrs, as the cobalt yields its arfenick, and the re- mainder, like that of the cobalt, is an earth eafily fufiblc into the fame blue glafs.

CADMIA Fomacum. Sec Tutty.

CADMITES, in natural hiflory, a kind of gem, nearly refem- bling the oftracitis ; from which it only differs in that the lat- ter ia fometimes girt with bluefpots. PUu, Hift. Nat. 1. 37. c. 10. See Ostracitis.

In fome MSS. for cadmites, we read calamity. Hardouhi. Not. adPlin. loo cit.

CACUEATOR, in antiquity, a_denomination given to heralds or meffengers of peace. Aauhu Lex. Milit. T. 1. p. 146. See Caduckus, Cycl and Suppl.

CADUCEUS {Cycl.)— F. Lafitau pretends to have found the caduceus amon^ the favages of America. The famous my- ftic tobacco pipe, or calumet, according to this author, is the true and original caduceus, of which the Greek and Roman ones were only types. Lafitau, Paral. des Moeurs. Sauv. ap. Mem. Trev. 1725. p. 216, feq. See Calumet. Wedelius has given a differtation exprefs on caduceated medals, De Nummis Caduceatis, Ext. in Ejuct. Exercit. Med. Dec. 6.

Ex. 5- P- 22 > fe 4- Caduceus is alfo a name given to a kind of ffaff covered with velvet, and decorated with flower de luces, which the French heralds of arms bear in their hands on folemn oc cafions. That born by the king at arms has a golden flower de luce at the end j and is by fome called fceptre. Trev. Diet. Univ. T. 1. p. 1322. Suppl. Vol. 1.

C M M

CADU3, KoJ©-, an antient liquid meafure of capacity, con- taining ten, fometimes twelve congii ; and fixty, or accord- ing to others, feventy-two fextaries. Linden, Exerc. to S HO. Got,: Med. Def. p. 292. Cafl. Lex. Med. p. ,20. Fab. Thef. p. 396. Piiifc. Lex. Ant. T. 1. p. 31 7. The cadm is the fame with what is otherwife denominated rnetretes ' and cerameon b , csV.— [« Gorr. Def. Med. p. 292. voc. p.rpiT,,-. i> Paul. Addit. ad Beverin. p. 135 ] St. Jerom alfo makes it the fame with the batus, or bath. H'uron. ad Ezech. c. 45. See Bath.

According to Beverinus, the cadm was different from the IMTgvrw, and contained three modii, or the third part of a corns ; and confequently, eighty pounds of water, or fixty of wheat ; being alio equal to the amphora. Beverin. Synt. de Ponder. P. 2. p. [34. See Amphora, Cycl. and Suppl.

CJECJE Glandula. See Glandule dscce.

CjECILIA, in zoology, the name of the flow-worm, or blind- worm, called by tire Greeks typhlima. It is a fmall fpecies of ferpent, which has fuch extremely fmall eyes, that it has been ufually fuppofed to have none at all. It is diftinguiflied from all our fnakes by its fmallnefs, and by the fliape of its tail, which runs out a great way beyond the anus, and yet is blunt and confiderably thick at the end. The colours vary much in the different fexes, and probably often alfo in the lame fex ; the common colour is a dufky greyifn yellow on the back, and the fides are variegated with ftreaks of black and white : it refembles the viper in its manner of producing its young, which are put forth alive. Say's Syn. p. 289.

Cecilia, in icthyography, a name ufed by fome authors for the fifh more ufually known by the name of the acta. Gefner, de pifc. p. 122s. See the article Acus.

CjECILIANA, in botany, a name ufed by Pliny and fome other authors for the Tut/an or androfamum. Gerr. Emac. Ind. 2.

Cj^ECUM inte/linum. SeelNTEsTlNUM Cacuni^

C/ELATUriA, or Coelatura, the art of engraving oh me- tals, ftones, woods, or the like, with inftrume'nzs of Heel, diamond, CSV. Libav. Synt. Arc. Chym. 1. r. c. 23. Cafl. Lex. Med. p. 120. Fab. Thef. p. 402. Pitijc. Lex. Ant. T. 1. p 313. See Engraving, Sculpture, (SV. Ctcl.

C/ELESTJANS, Cbslestiani, or CiELESTil, antient here- tics, the followers of Czeleftius, a monk, who flourifiied un- der the empire of Arcadius, about the year 40=;, and taught moft of the fame errors with Pekgius. See Pelagians, Cycl.

The Cee'.ejliani afferted, that no man need fin unlefs he will ; and that it is in every perfon's power to be righteous, and ar- rive at a ftate' of perfeflion, if he do his utmofl ; laftly, that man may fulfil all the commands of God without divine grace, and obtain falvation by his own works alone. The Ceelefiiqns were condemned with the Pelagians at the council of Ephefus. Their arguments were refuted by St. Auguifin, whom St. Jerom compliments as having driven the Ctzlejliam off the ftage. Prated. Elench. Haeref. 1. 2. p. 1 2.6.

CLEMENT, or Cement, the folution of metals by acid men- ftrua, fuch as aqua fortis, fpirit of nitre, and the reft, is a thing commonly practifed and well known ; but thefe men- ftrua all evaporate over a fire ftrong enough to make them boil ; and yet it was found neceffary for the metallurgifts and affayers to know the efle&s of the fame menftrua in a much ereater degree of heat ; and as this could not be given them in their fluid form, by reafon of their evaporation, they have found a method of ufing the ingredients which afford them in their dry ftate :^ thefe ingredients thus ufed are called cements, and the operation cementation.

It was foon found, that the acid falts, when condenfed into li- quors, could not bear any great degree of fire, but were by it refolved inro vapours, and flew off; yet that thefe very li- quors or acid fpirits, could not be feparated from their falts but by a very violent and ftrong fire ; and thence it was learned, that to have the effeefs of thefe powerful menftrua, with tha effecb of a ftrong fire at the fame time, it was neceffary to u(e, not the menftrua already extracted in a fluid ftate, but the ingredients from which they were to be made in their dry form. The bodies therefore to be thus wrought upon by the acid fpirits, and by a violent fire at the fame time, muff be put into the veflel wherein the faid fpirits are produced, that be- ing made red hot therein, they may be furrounded on every fide by the agitated vapours of thefe fpirits : this is eafily done by firft flightly moiftening the matter which affords thefe acid fpirits, then preffing tile mixture a little, and expofino- the metal mixed with this matter to the fire.

The proportion of the ingredients and additions to them, ufed in making cements, is much the fame as in the diftillation of the acid fpirits from the fame ingredients ; but common fait nitre and vitriol, being the melting menftrua of metals' and vitriol being apt to become extremely hard, by the fame' fire which is proper to be ufed in cementations, that is not a very violent one, on this account they ufe a quantity of brick-duft or other fuch fubftance with them, three or four times greater than their own ; left: the falts melting by a fomewhat ftroneer fire being employed, fliould put the metals, efpecially gold and filver, in fufion: but by this method you prevent the ° A melting