A G A 



mended both by the author aiut by Kiinkcl, as prodnciiipf 

 a compofkioii for i'pleiulour and vividncfs of colour often 

 fiipcrior to real agate. Take feven ounces of gianulatid 

 filver, and five ounces of mercury, four drams of minium, 

 one ounce of verdegns, and Icales of copper, crude anti- 

 mony, and black manganefe, of each iialf an ounce ; didolve 

 the filver by itfelf in nitrous atid, and having ground the 

 rell of the materials together, add firll two pounds of nitrous 

 acid, and tlien the nitrated lilvcr, mixing both litjuors evenly 

 and intimately with the other fubllanees ; then difPolve 

 two drams of gold in nitro-muriatic acid, and grind together 

 the following ingredients ; viz. cinnabar, twelve drams ; 

 fulphuraled oxyd of copper, twenty drams, fulphurated 

 oxyd of iron, four drams, and white oxyd of tin, oxyd of 

 iron, iron fcales, zaffrc, orpiment, and white arfcnic, of 

 each lialf an ounce ; mix the lolution of gold with this com- 

 pound powder, and then add thrice its weiglit of nitro- 

 m\iriatic acid : digeft in fcparate glafs veffels for twenty- 

 four hours in a fand-bath the above nitrous and nitro-mu- 

 riatic mixtures, then add them together, and diftil to dry- 

 nefs ; there will remain a powder of a reddifli green colour. 

 Alfo take twenty pounds of clear flint glafs, and reduce it 

 to a fine powder, in a clean fteel mortar, add to this two 

 ounces and a half of the above colouring cmnpofition, and 

 flux them together ; when the whole is in clear fufion, flir 

 it up from the bottom and let it continue melted for twentv- 

 four hours, then IHr it again, and allow it to cool very 

 gradually ; its colour will then be a middle tint between 

 yellow and blue. Place the crucible again in the fur- 

 nace, and when the glafs is melted, add, at five or fix diffe- 

 rent times, the following mixture ; calcined tartar, eight 

 ounces, vitrified wood foot, two ounces, and half an ounce 

 of perfect oxyd of iron : this will make the glafs fwell con- 

 fiderably, and therefore requires much care to prevent it 

 from flowing over : when all is quiet, heat it well for 

 twenty-four hours longer without touching it, and it will 

 then be fit for ufe. Kirwan Mineralog. — Kirwan Geolog. 

 Efs. — Lametherie Theorie de la Terre. — Lewis's Commerce 

 of Arts. — Neri fur la Verrerie. 



Some writei-s have diilributed agates, with regard to 

 the objects that are reprefented upon them, into arbo- 

 refcent, as dendrackates and dendrites ; horned 

 or cERACHATEs ; aphrodifian, a term given by Velfchius 

 to an agate in his cullody, of a flcfli colour, with a half 

 moon on one fide i-eprefented by a milky femicircle, and on 

 the other, the phafes of Vefper, or the evening-fl:ar ; cor- 

 foid, witii human hair ; arithmetical, with the numbers 

 419 1, 191 (Settala. Muf. 81.) ; aflronomieai, with the 

 hemifphere and its feveral orbs, and the earth in the middle; 

 anthreipomoi-phous, with the figures of men or women, one 

 of which, mentioned by Kircher, reprefents a heroine arm- 

 ed ; and another, in the libraiy of Francfort, exhibiting 

 the heart, lungs, and part of the veins of a man ; but the 

 moft celebrated of this kind is that of Pyrrhus, reprefent- 

 ing the nine Mufes with their attributes, and Apollo in the 

 iniddle, playing upon the harp (fee Plin. 1. xxxvii. c. 3. 

 Hard. Not.) ; leucophthalmous, bearing the figures of eyes, 

 as of birds, firties, and wolves, called by Cardan and others 

 lycophthalmi, of goats denominated aegophthalmi, of oxen 

 boophthalmi, &c. ; the Tiberian agate in the treafury of 

 the French king's chapel, reprefenting the apotheofis of 

 Auguilus, and the feries and portraits of the family of Ti- 

 berius and Julia, with divers foreign nations fubdued in v>-ar, 

 concerning which, many different conjeftures and explica- 

 tions have been advanced by the learned ; and the luac 

 agate, a curious antique at Rome, fo called, becaufe it re- 

 prefents the head of Ifis, and dillinguifhed by the epithet 

 annularis, as being fet in a ring. However, in this kind of 



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diHribution, and in the denominations to which it has giveit 

 occafiou, the imagination has often mifled the judgment. 



Beccaria obfervcs, that the cleftric fparks will not be 

 conducled by the fiirface of poliflied agates ; and M. Bofe 

 has fliewn, that the agate was very early known to poffefs 

 eleftiical powers. 



Agate, among y^iitiquaries, denotes a ftonc of this kind, 

 engraven by art. 



In which fenfc agates make a fpecies of antique gemr. ; in 

 the workmanlhip whereof, we find eminent proofs of the 

 greatell flcill and dexterity of the ancient fculptors. Se- 

 veral agates of exqulfite beauty are preferved in the cabinet* 

 of the curious. The fafrts, or hillories, reprefented in 

 antique agates, with how much addrels foever condufted, 

 are become, at this diilance of time, many of them ob- 

 fcure and dubious, and their explication difficult enough ; 

 whence divers millakes have been committed, and numcron* 

 conjeftures and difputes raifed. Hill. Acad. R. Infer, tom. i. 



Agate, is alfo the name of an inllrument ufed by gold- 

 wire drawers ; fo called from the agate in the middle of it, 

 which forms its principal part. 



AGATHA. See Achates. 



Agatha, St. in Cvo^^vrpby, a fmall town of Naples, in 

 the farther principality, on the confines of Terra di' Labora, 

 between Capua and Bencventum, eight leagues, north-eaft 

 of Naples. N. lat. 40" 55'. li. long. 14°"2 2'. 



Agatha, in ylndcnl Geography, a city of Gallia Narbo- 

 nenfis, built by the MafTylians, mentioned by Pliny, (lib. iii. 

 c. 4.) and by Strabo, (tom.i. p. 272. 276.) See Agde. 



Agatha, \i\ Natural H'ljhry, a fpecies of the Papilio 

 Nymphalis, with dentated wings, the upper part yellow, 

 the under grey ; and the poflerior wings have one black, 

 fpot above, and three fpots beneath. It is found in 

 India. 



AGATHARCHIDES,orAGATHARrHus of Cnidus, 

 in Biography, a Greek hillorian, grammarian and rhetorician, 

 mentioned by Jofephus, (antiq. 1. xii. c. 1. tom. i. p. 585. 

 Cont. Appion. 1. i. tom ii. p. 457. Ed. Hard.) Diodorus 

 Siculus, (Bibl. Hift. tom. i. p. 50. p. 181. Ed. Wefl"el.) 

 Strabo, (tom. ii. p. 969. p. 1 125. Ed. Cafaub.) Lucian, 

 (tom. iii. p. 222. Ed. Reitz.) and other ancient writers, 

 was contemporary with Eratotlhenes, though younger than 

 him, and flouriflied under Ptolemy Philometor, about 177 

 years before Chrill. He was reader to Heraclida, and pre- 

 fident of the Alexandrian Library, and wrote feveral hif- 

 torical treatifes ; of which Photius mentions 49 books, 

 concerning the affairs of Europe, 10 of Afia, five of the 

 Red Sea, and an epitome of what had been v/rlttcn on this 

 fubjeft in one book. Some fragments of his writings may 

 be found in Jofephus (uh'i fvpra), and Photius in his Eiblio- 

 theca, 213. 250. Fabric. Bib. Grcec. tom. ii. p. 207. 

 The teflimony of Agatharchides is alledged by a learned 

 writer to prove, that in the reign of Ptolemy Philometor, 

 146 years after the death of Alexander, the Greek fo- 

 vcrcigns of Egypt had not yet traded direii'ly to India, but 

 imported the commodities of India from Saba, the capital 

 of Yemen. This ancient vv.'ter's defcription of the wcftern 

 coafl of the Red Sea doles at Ptolemais, as if there were 

 no regular commerce beyond that point. See Vincent's 

 Periplus of the Erythrean Sea, part i. p. 31. 



AGATHEMER Orthonis, a geographer, who lived, as 

 fome fay, near the time of Septimius Severus, and accord- 

 ing to others, in the 15th centuiy. Pie wrote in Greek two 

 books of a compendium of Geography for the ufe of his 

 pupil Philo, which is commended by J. Vofidus, L. Plolfte- 

 nius and G.Wendelinus, and which was firfl publiflicd in Svoi 

 with a tranflation and notes, by Tennulius, at Amfterdam, in 

 167 1 ; afterwards by Gronovius in 410. at Leyden, 1697 ; 



and 



