G L E
G L O
Iron-colour Glazing is prepared of fifteen parts of lead afties, fourteen of white fand, five of copper afties, one of manga- nefe, one of zaffer, and one of iron filings.
Liver coloured Glazing is prepared of 12 parts of litharge, eight of fait, fix of pebble or flint, and one of manganefe.
Purple brown Glazing confiifs of lead afhes 15 parts, clear fand 18 parts, manganefe one part, white glafs 15 meafures, and one meafure of zaffer.
&^Glazing is made of antimony two pounds, litharge three, and ruft of iron calcined one ; grind them to a fine powder.
Sea-green Glazing is made of five pound of lead allies, one pound of tin afhes, three pound of flint, three quarters of a pound of fait, half a pound of tartar, and half a pound of copper duff.
White Glazing. A fine white glazing for earthen ware is thus prepared. Take two pounds of lead, and one of tin ; cal- cine them to afhes : of this take two parts, calcined flint or pebble one part, and fait one part, mix them well together, and melt them into a cake for ufe
The white glazing for common ware is made of 40 pound of clear fand, 75 pound of litharge or lead afhes, 26 of pot- afhes, and ten pound of fait : thefe are three times melted into a cake, quenching it each time in clear cold water. Or, it may be made of 50 pound clean fand, 70 of lead afhes, 30 of wood afhes, and 12 of fait.
Yellow Glazing is prepared of red lead, three pints; anti- mony and tin, of each two pound. Thefe muff be melted into a cake, then ground fine ; and this operation repeated feveral times. Or, it may be made of 15 parts of lead ore, three parts of litharge of filver, and 15 parts of fand.
Citron yellow Glazing is made of fix parts of red lead, feven parts of fine red brick-duff, and two parts of antimony. Vid. Smith's Laboratory,
GLECHOMA, in botany, the name by which Linnseus calls ground-ivy. See Ivv.
GLECHONITES, a name given by the antient phyficians to a fort of wine impregnated with penny-royal, much recom- mended in all obftrucfions. It takes its name from gle- ebon, the Greek name of penny-royal or pulegium. See Pulegium.
GLEDISTIA, in botany, a name given by Clayton to the plant called cefalpinoides, by the author of the Hortus Clif- fortianus, and others. The characters of the genus are thefe : it produces feparate male and female flowers ; the male are clofe and compact amenta, and the females more open and loofe ones, but both are pendulous. In the male amentum, the peculiar cup of every flower is erect, and open, aHd is compofed of one leaf, divided into four con cave fegments. The flower confifts of four petals, of ai. oval figure, but very narrow, and fomewhat hollowed ; the Aamina are fix (lender filaments longer than the flower, and the anthene lie upon them. Linneei Gen. Plant, p. 481. In the female flower the cup is of the fame ftrudture with that of the male; the flower is alfo compofed of four like petals, but they are much larger, and there are in the bafe of this flower two (lender nectaria-like filaments; the germen of the piftil is broad, and comprefled, and is longer than the flower ; the ffyle is long, the ftigma lies upon it, and is large and crooked : the fruit is a very large and broad pod, of an extremely compreffed figure; there are feveral tranfverfe fepta in it, and the cells between them are filled with pulp , in each of thefe there is alfo contained a fingle ked which is roundifh and very hard. Hort. Cliffort. p. 489.
GLESUM, otglmfum, in natural hiftory, a name given by many of the antients to the common yellow amber or fuccinum. The word feems to'have been originally German, and to have been adopted by the Romans in their conquefts in that part of the world. They feem to have ufed the word in general for any tranfparent fubftance, and thence to have applied it to amber as a tranfparent done. The ifland Auftravia of the Germans afforded a very great quantity of fine amber on its fhores, and the Roman foldiers thence gave it the name of Clafaria. This is a proof of the word gleftim, being re- ceived into common ufe as the name of amber. Pliny tells us, _ that this ifland was called by the Roman foldiers GU- faria, becaufe of the great quantity of fuccinum found in it ; and that by the barbarous natives, that is the Germans of thofe times, it was called Auftravia. The finding amber in plenty on this ifland, on which there grew alfo a great num- ber of pines of a fpecies not known to the Romans before, gave origin to an opinion that prevailed a long time among them ; that is, that the amber was the condenfated refin o? this tree. Pliny fays, that the refin of this tree fweating out of its cracks and chinks in the heat of the autumn, and falling into the fea, was there tofled about and hardened by the water; and finally, fo concreted by the cold wea- ther, as to acquire the ftony hardnefs we fee in it; and it is in this fenfe that the Roman authors tell us, that the difco- very of the true nature of amber was owing to Caifar Ger- manicus, who difcovered this new fort of pine in the amber country.
Pliny alfo tells us, that the gtefum, or amber, was produced in India, and relates a ftory of Archelaus, a governor of a
province, who fent from thence a rude of rough mafs of amber to Rome, with the bark of the pine tree, from which it had exfudated, yet remaining affixed to it. This mi»ht feem a proof of its being the gum or refin of a tree ; but when we confider the inaccuracy of the writers of that time it will have but little weight againft the modern fyftcm of amber being a true and genuine mineral. The ftory mWit poflibly not be true ; or if fo, the amber might be onlv ad- hering to that fort of cortical fubftance refembling the barks of trees, among which it is found foffile in PruiTia at this time. This fubftance is not the bark of any tree, though it much refembles it. Finally, it might not be amber which this governor fent to Rome ; but fome Indian gum, of which there are two or three fo like amber, that nothing but expe- riments can (hew that they are not fo, and this might very naturally be fent with the bark of the tree, which produced it, yet adhering to it. Tacitus tells us, that the amber brought from Germany was rough or rude, but he does not fay any thing of its having any bark adhering to it.
GLEUCINUM, a term ufed by the old Greek writers, to ex- press a compofition made of the oil of. unripe olives, in which there were infufed fchaenanth, fpikenard, and many other of the aromatic drugs, with a confiderable quantity of mufk ; all thefe were put together into a vefl'el, which wes furrounded with the prcflings of grapes, the fermentation cf which gave it a gentle heat ; and it was left thus thirty days, being well ftirred about every day : at the end of this time it was ftrained off', and the clear oil referved for ufe. It was efteemed warming, emollient, and relaxing, and was ufed externally in many cafes.
GLINUS, in zoology, a name by which Bellonius and fome other authors have called a finall fea filh, more commonly known by the name of the dracunculus,
GLIS. In the common acceptation of the word, this only fignifies the dormoufe. But Linnaeus has ufed it in a larger fenfe ; and, in his fyftem of zoology, makes it the claflical name of a fet of animals. The characters of the creatures of this clafs are, that they have only two fare teeth in each jaw, they have no dentes canini or dog teeth, and have all eight paps placed on their belly. The animals of this clafs are the feveral fpecies of the porcupine, the hare, the fquir- rel, the beaver, and the moufe and rat. Linnzi Syftem. Natur. p. 38.
Glis is commonly ufed as the name of an animal of the moufe kind ; but fo differently defcribed by different au- thors, and fo imperfectly and erroneoufiy by many, that it is a queftion whether we can properly call any known ani- mal by the name.
Gefner defcribing it by hearfay, fays, that it is larger than a fquirrel, and either black, or brown on the back, and white on the belly, its tail fhort, and its general figure fomewhat approaching to that of the bear. Hay's Syn. Quad. p. 230.
Glis Volans, The flying dormoufe, in zoology, the name of an animal, properly of the vefpertilio or bat kind ; it is diftinguifhed, by Linnaeus, by the name of tiefpertilio cau- datus najofoliato obverfe eordato. Seba, Vol. I. p. 9. Linnai Syft. Nat. p. 37.
GLISCHROCOLOUS, an epithet ufed by fome writers, to exprefs excrements which are at once vifcid, and very highly fated with gall.
GLISCHROMICTHES, in natural hiftory, the name of a ge- nus of compound earths. The word is derived from the Greek -,?.ioze®- tough, and (ii*Sin mixed. The bodies of this genus are loams compofed of fand and a more vifcid clay, and are of a tough and firm texture. The earths of this genus are ufed in making bricks, and on fome other occaiions, and are of feveral diftinct fpecies. I. A greyifh white one, dug in many counties of England, and making a very firm brick. 2. A pale yellow one, dug plentifully in the neighbourhood of London, and making a fine red brick. 3. A yellowifh brown one, frequent at finall depths in all parts of the kingdom. 4. A redifh brown one, dug in Staffordihire, and fome other counties, and fliewing itfelf in fome places on the furface in the roads. Hill's Hill, of Foil', p. 429.
GLISOMARGA, a word ufed by fome authors as a name for chalk. Sec Chalk.
GLISSA, in zoology, the name of a fea fifti of the tunny kind, but of a perfect ly fmooth fkin, and wholly free from fcales. It ufually grows to the length of two cubits, and the thicknefs of a man's body. It is of a very round body, and has very rough jaws, but no did inct tec-Lb" ; its tail is forked, but not fo arched or lunated as that of the tunny ; it lives in deep water, and is a fiifl of very delicate tafte. Gefner dc Pifc. p. 1 158.
GLOBE (Cyel.) — Our common globes, though inftructivc inff ruments for explaining the firft rudiments of geography, and the fpherical doctrine of aftronomy, yet labour under feveral defects, as they do not fhew how the phenomena arife from the motion of the earth, which is one of the chief points beginners fhould have in view. Mr. Jofeph Harris has therefore contrived to remedy thefe defects, in the philo- fophical Tranfactions, N° 456. Sect. 7.
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