Page:Cyclopaedia, Chambers - Supplement, Volume 1.djvu/815

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They then mix with every ten grains of gold one grain of i cerufs, and incorporating the whole with gum water, they! lay it on in the manner of other colours. There have been many methods of imitating the colour and appearance of gold in the bafcr metals, but none of them come up to that of Mr. Homberg, which is performed in this manner : make an amalgame of one part pure copper and three parts quickfilvcr, boil this in river water for two hours, then diftil off the quickfilvcr, and cohobatc it once ; take out the copper, and fufe it, and it will be found of a beautiful gold colour, and more ductile than common copper under the hammer, and is extremely fitted for watch-work, gild- ing, and the finer machines and utenfils. Shaw's Lec- tures, p. 282. Gold ore. They have one way of working this ore at Chrem- nitz in Hungary, which is very fingular, as no lead is em- ployed in the whole courfe of the work. They wafh the pounded'ore very often, and lay it in powder upon cloths, and by the gentle and oblique defcent of the water over it, and their continual ftirring of it, the earthy, clayifh, and lighter parts are all clean warned away, while the heavier and metalline remain in the cloth. Not much unlike to this proceeding is that with fheeps fldns and wool, which they place either in the water that comes from the works, or in the ftreams of rivulets, which have their origin in hills where there is much gold ; fo that while the water or fluid parts pafs through or over them, the more folid, heavy, and metalline are infnarcd and detained, and by this means the fkin becomes a golden fleece. The cloths which are by the Chremnitz works in this manner impregnated with gold, are wafhed in large tubs of water, and after fettling, the water is decanted ftowly off; the fediment which is left behind is, after this, wafhed in three or four other waters, and to the "clean remainder they add quickfilvcr, which they then work and knead into an amalgam, like dough or pafte. When they have worked this together for an hour or two, they throw it into water, and waih off the quickfilver, which did not adhere, and then there remains a pure and perfect, mafs of the amalgam. They fqueeze as much of the quickfilver as they can from this, firft through coarfe cloths and then through fine ones, they then put the remainder on a perforated plate, which they place over a deep pan, fet in the earth, in the bottom of which there is put fome quickfilver ; they then cover with a hollow earthen lid, luting it carefully on, and when the lute is dry they make a charcoal fire over it. By this means the quickfilver yet remaining with the gold in the amalgam is driven off, and runs down through the holes of the plate, mixing itfelf with the reft in the bottom of the pan, and the gold is left alone in a fpungy mafs, which only needs once melting in the common way to be pure and malleable gold. Brown's Travels, p. 67. GoLD-fncb. This bird is particularly fond of the buds of the goofeberry tree. They often come in whole droves at once into gardens, and will clear away all the buds from the trees in a few days ; they are eauly Jliot, but the trees are ufually injured by this, fo that it Is better to lime the twigs. Jldor- tifner's Hufbandry. Gold fijh, in zoology, a name by which fome authors have called the alaufa or mad, from the yellow colour it fre- quently has on the covering of the gills. See the articles Alausa and Agonus. GoLD^Zf. The method of making gold Jize for burnifhed gilding or wood is this : take a pound and a half of pipe clay, half an ounce of red chalk, a quarter of an ounce of black lead, forty drops of fwect oil, and three drachms of pure tallow ; grind the clay, chalk, and black lead, all feparately, very fine in water, then mix them together, and add the oil and tallow, and grind all to a due confiftence. This is the fize now in ufe, and is accounted the better the older it is. tsoLD-fmitb, or as fome chufc to exprefs Itjtfofr-jmhth-i the artift, who makes veffels, utenfils, and ornaments in gold or filver. The goldfmiths work is either performed in the mould, or beat out with the hammer, or other engine. All works that have raifed figures are can: in moulds, and after- wards polilhed and finiflicd ; plates or dimes of filver or gold are beat out from thin flat plates, and tankards and other veffels of that kind are formed of plates foldered together, and their mouldings are beat, not call:. The bufinefs of the goldfmitb formerly required much more labour than it does at prefent, for they were obliged to hammer the metal from the ingot to the thinnefs they wanted ; but there are now in- vented flatting mills, which reduce metal to the thinnefs that is required at a very fmall expence. The goldfmitb is to make his own moulds, and for that reafon ought to be a good defigner, and have a tafte in fculpture : he alfo ought to know enough of metallurgy to be able to affay mixed metals, and to mix the alloy.

The goldfmitb in London employs feveral hands under him for the various articles of his trade. In this great city there are always hands that excel in every particular branch of the trade, and there is commonly employment enough for every one in his particular branch. The jeweller, the fhuft-box and toy maker, the filver turner, the gilder, the burniiher, the chafer, the refiner, and the gold beater, are all em- ployed by and under the goldfmitb.

GOLDEN (Cycl.) — Golden eye, in ornithology, the Eflg- fifh name of a fpecies of fea duck,_ called by authors clangula-, It has its Englifh name from the beautiful yellow of the iris's of its eyes. See Tab. of Birds, N a. 50. the article Clan- gula.

Golden^, is alfo ufed for a fpecies of fly. See Chrysopis.

Golden fleece : Suidas imagines that the golden fleece which Jafon and the Argonauts carried over the Pontic Sea from Colchis, was only a book written on fkins, which taught the manner of making gold by the chemical art. This, if proper vouchers could be given for it, would carry back the antiquity of chemiftry very far indeed, even thirteen cen- turies before Chrift, in which time the fcience muft have been both known, practifed, and even written of, fo as to prove the occafion of this painful and hazardous expedition. But what difcredits all thefe accounts, is, that Mofes and the other facred writers, as alfo Sanchoniatho, Orpheus, Homer, Pindar, Hefiod, Herodotus, Thucydides, Hippo- crates, Ariftotle, Theophraftus, Diofcorides, Galen, and Pliny, are all utterly filent on this head j when the age3 they lived in, muft have given them opportunities to have fpoken of it in their works. The malleable glafs mentioned by Pliny, and Caligula's extracting gold from orpiment, are only proofs that they were great mafters in the art of glafs and affaying. Bocrhaave's Chcm. p. 17.

Golden bead, in zoology, a name by which fome have called the anas artica clufii, a web footed fowl, common on our fhores. See Duck.

Golden rod, virga aurea. We have feveral very beau- tiful fpecies of this plant cultivated in our gardens, where they are very great and lifting ornaments, beginning to flower in May, and one kind or other of them continuing flowering till October. See Virga aurea.

They are all eafily propagated by parting their roots in fpring, before they begin to flioot ; they will grow in any foil, or fituation, but they fucceed beft in a light frefh earth and an open expofure, and fhould be planted in the middle of large flower beds : they are perennial plants, dy- ing down to the ground, as foon as they have ripened their feeds, but rifing again the following fpring. Thefe feeds fown will very freely "row, and often produce varieties in the flower. Miller's Gardners Di£t.

Golden Saxifrage, in botany. See Chrysosplenium.

GOLTBERGENSIS terra, in the materia medica, a whitifh earth, ufed in the fhops of Germany and Italy as an aftrin- gent, a cordial, and a fudorific, but little known among the Englifh apothecaries. It is dug in many parts of Germany, but particularly at this time in the neighbourhood of Hoffel, in the bilhopric of Liege, in the circle of Weftphalia. It is taken up there in confiderable quantities, and ufually is fealed with the impreflion of an eagle, and with its old name goltbergenfis terra under it. It is imagined to contain fome particles of filver, and thence to derive fome of its virtues* It is a denfe compact earth, of a dull greyiih white, foft and friable, and adheres firmly to the tongue, and makes no cf- fervefcence with acids. Hill's Hiff. of Foflils, p. 4.

GOMARA, or Gomaris, in natural hiftory, a name gi- ven by fome of the old authors to talc ; fome have alfo called it gamara : this laft feems only a corruption of the word gomaris, and that of comaros or comaris, a name this ftone ■was often called by among the Greek writers of the middle ages. Some have alfo called the felenites by this name, and it feems to have originally belonged to that fofiile ; but both being foliaceous foflils, both were often con- founded together. GOMATUS, in zoology, a name ufed by many for the gurnard, more frequently called by authors gurnatdus. Ray's Ichthyog. p. 279. See the articles Gurnard and

CUCULUS Pifcis.

GOMPHASIS, a word ufed by the old Greek phyficians for a pain in the teeth, and fometimes for their being loofe in their fockets.

GOMPHII, a word ufed by the old Greek writers for the denies molares.

GOMUTTRA felagina, in natural hiftory, the name given by the Indians to a kind of foflil, found in great plenty on the mount Vindy in the Eaft-Indies, in places, as they ob- ferve, where the cows frequently urine. It is a bituminous fubftance, and after calcination the refiduum is given in cafes of internal ulcers and in gonorrhoeas. The Indians fuppofe it is formed by the drying up of the cow's urine.

GONAMBUCH, in zoology, a name by which many called the guainumbi, or humming bird j the fmalleft of all birds. See the article Guainumbi.

GONANDINA, the name of a Brafilian tree, remarkable for its great height.

GONDOLA Jl)cll, in natural hiftory, a name given by au- thors to a peculiar kind of concha ghbofa ; fappofed, in fome degree, to reprefent the fhape of a Venetian boat. It is of the genus of the dolium, and there are feven fpecies of it. I. A grey thick one. 2. A long Ihaped greenifh one. 3. An oblong reddiih one. 4. A thin white papyraceous one. 5. A yellow one, with four brown circular lines. 6. A brownilh one, with capiliaceous ( lines. 7. A white one umbilicated on each fide. Thefe are called by the Latin

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