Page:Cyclopaedia, Chambers - Supplement, Volume 1.djvu/837

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authors to the zeopyrum, or hordeum nudum, the naked barley. Chabraus, p. 175.

GYMNOPODIA, rjpwnfea, among the antients, a kind of fho.es which difcovered the naked feet. They were worn by the Grecian women, who affected them much. Hoffm. Lex. in voc.

GYMNOPYRIS, in natural hiftory, the name of a genus of fo fills, the characters of which are thefe. They are of the clafs of the pyritse, and are compound, inflammable metallic bodies, found in detached manes, of no determi- nately angular figure ; of a fimple internal ftructure, not ftriated ; and are naked, or not covered with any inveftient coat, or cruft, in which they differ from the pyriplaces. See Tab. of Foflils, Clafs 5. HUP* Hilt, of Foil*, p. 614. Of this genus there are only two known fpecies. 1. The green fmooth variously fhaptd gymnopyris } and 2. the gymno- pyris with a botryoide furface. The firft of thefe is the moft common of all the pyritse, and appears to be under a great variety of fhapes. It is a very hard and firm body, of a compact and clofe texture, and very considerably heavy. It is found in mafles of various fizes, from half an inch to ten inches, or more, in diameter, and is ufually of a Come- what flatted; form, and of an undulated, or rigid furface, though not unfrequently it emulates the fhape of the com- mon pebbles, and often is perfectly fmooth. Its furfaces arc never very rugged in their native ftate, and when broken, it appears of a fmooth even ftructure, and is both within and without of a pale filvcry green. It cracks and burfts in the fire, and yields a deep blue flame, and finally burns to a purple powder.

It is very common in the ftrata of tile clay in all parts of England, and mews- itfelf there in a number of various fhapes and forms, very often having formed itfelf in the cavities of fea fhells buried there, and fiuce perifhed; but moft frequently of all in the pores of wood, pieces of branches of trees, and even of old boards, being frequently wholly fa- turated with it. All thefe as well as the fubftance in its native ftate, readily moulder away on being expofed to a moift air, and are then found very pregnant with vitriol. It is from thefe, and particularly from the foffile wood, impreg- nated with this pyrites, that the green Englifh vitriol, or common copperas, is made at Deptford, van: quantities of foffile wood thus impregnated, being lodged in the ftrata of clay in the cliffs of Sheppey ifland and elfewhere, which the fea at times wafhes out, and leaves fcattered about the more, and which are there gathered by people employed for that purpofe.

The fecond fpecies, or botryoide gymnopyris, is a very ele gant and beautiful foflil. It is very hard and heavy, and L very irregular in fhape and fize ; but moft frequently met with either in oblong, or fomewhat globular pieces of many pounds weight; though fmallcr, and thofe very elegant flatted fpecimens, are not uncommon. It has naturally no coat or cruft, but when it has been long expofed to the air, it fometimes acquires a brownifh ruft, like that of iron which covers it and looks like one. When broken it appears the moft uniform and regular in its ftructure of any of the pyrita?, looking like a mafs of forne melted metal. It is ufually of a pale filvcry green, though fometimes of a deeper brownifh one; but what abundantly diftinguifhes it from all the other pyritae, is, that its furface is ever beautifully ele- vated into a number of tubercles, of various fizes, but of irregularly roundifh fhapes ; and fometimes not only Its fur- face but its whole fubftance is thrown into thefe forms. Hence it is, that it refembles clufters of grapes, hanging very thick upon the branches. It is frequent in Yorkfhire, nor lefs fo in Devonfhire and Cornwall, and there is a great deal of it in the clifts of Sheppey ifland, but there the fpecimens are ufually fmall.

GYMNOSPERMlA, in botany, the name given by Lin- nasus to a certain feries of plants of the didynamia clafs. This clafs, according to that author, comprehends the plants with labiated and perfonated flowers : thofe with la- biated flowers always have four feeds fucceedino- each flower and thefe are placed without any capfule or covering in the bafe of the cup. Thefe are therefore called gymnofpermia or naked feeded, whereas the others which have perfonated flowers, have the feeds inclofed in capfules, and are there- fore called angiofpermia. See Didynamia. GYMNOTUS, in ichthyology, the name of a genus of fifties, the characters of which are thefe. It is of the mala- copterygious kind. The branchioftege membrane contains five bones, and it has no fin upon the back. There is only one known fpecies of this genus. It is an American fifh, defcribed by Marggrave, under the name of carapo. Artedl Gen. Pifc. 22.

GYN./ECOCOSMI, iwuuxmtpsi, m antiquity, Athenian magiftrates, whofe bufinefs it was to regulate the women's apparel, according to the rules of modefty and decency.

SeeGYNJECONOMUS, Cycl

GYNjECOMASTOS, a term ufed by the antients, to ex- ( prefs a man, whofe breafts are large and turgid like thofe of women, and afford milk.

It was an obfervation among the antients that fuch men Suppl. Vol. I.

were naturally impotent. Paulus ^Egineta obferves, that the breafts of men as well as women fwell at the time of puberty, but that thofe of women continue fwelled, and thofe of men fubfide again, except in the cafe of the gyna- comajioi., where they remain turgid, and become in time more and more fo, as the fat increafes under them. As this fwelling of the breafts gave a fufpicion of impotency, thofe who laboured under that deformity, ufually had recourfe to a very painful operation in furgery to get rid of it. An in- cifion was made in the form of a crefcent in the lower part of the breaft, then the fkin being drawn back the fat was taken out, and the lips of the wound healed by means of a future. When the breafts were very large, and hung down, they made two incifidns, one within the other, meeting at the extremities, and then feparating all the fkiri between them they took out the fat : and finally, if the difeafe returned, or they had performed the operation imperfectly, leaving fome behind, they repeated the whole a fecond time. GYN7ESIA, a word ufed by the writers in medicine, fome- times for the menftrua and fometimes for the lochia. See Menstrua and Lochia.

GYNANDRIA, in botany, a clafs of plants, in which the male and female parts of the flower are joined at their ori- gin, the ftamina or male parts of which grow to the pi- ftillum or female part, and not to the receptacle of the feed. The word is formed of the Greek ywn female, and «n»g male. Among the plants of this clafs are the pafllon flower, birthwort, &c.

The general character of this clafs of plants is very obvious : they are diftinguifhed at firft fight from all others, by the ftamina being placed upon the ftyle ; or, in other words, the receptacle is elongated into the form of a ftyle, and bears on it both the piftil and ftamina.

The order of the diandria, the firft of this clafs, is a very natural diftindtion among plants, and its genera differ from one another in no other grand particular, but the nectaria. Botanifts, in general, have judged the roots of this order of plants, which are either tefticulated, or palmated, to be a very certain mark of diftinction : but this obfervation, of the difference of the nectaria, which is owing to Linnseus, is much to be preferred, as being both more certain and more obvious. The ftrudture of the fructification, in this order of plants, is very Angular. The germen of the piftil is always contorted, and the petals are five in number : the two external ones often form themfelves into a galea, the lower lip of which forms the nectarium, which fupplies the place of a fixth petal and a piftil. The ftyle is affixed to the in- terior margin of the nectarium, fo that it and its ftigma are fcarce to be diftinguifhed in the flower. The ftamina are always two filaments, very fhort, and fupporting two an- therae, which are of a narrow fhape below, and are naked, and divided into feveral lobes, in the manner of the pulp of an orange. Thefe are covered each with a fmall cell, which is open downwards, and growing on the inner margin of the nectarium. The fruit or feed veffel is a capfule, containing only one cell, and formed of three valves. The feeds are very numerous, and as fmall as grains of duft, and are af- fixed to a {lender receptacle, which is placed within each valve. All thefe plants are extolled by authors as provo- catives. Sec Tab. 1. of botany, Clafs. 1. The flowers of all the plants of this clafs have a ftrange and, as it may be called, monftrous appearance, very different from that of all other plants in their flowers ; but this is only owing to the Angular difpofition of the parts of fructification in thefe flowers, as defcribed above. Linnesi Gen. PI. p. 451.

GYPSINE jlone, a name given by fome writers to the gyp- fum, or foffile fubftance, of which the powder called plaiiter of Paris is made by calcination. There are in many parts of Arabia vaft rocks of this ftone ; it refembles alabafter, but is fofter, and of a more lax texture. It is found to be a very eafy ftone to form by tools, and therefore the Arabs build with it in fome of the places in the neighbourhood of the quar- ries, but they are forced to make the walls very thick, as the ftone is fo foft and crumbly. The building called Arfoffa, or Arfoffa Emir, which feems the remains of a monaftery, is built wholly of this ftone ; and when the fun fhines upon it, the walls give fuch a luftre, that they dazzle the eyes ; but the foftnefs of the ftone, and the rednefs of the mortar, have confpired to make it a very ruinous pile at prefent, though of no great antiquity ; the ftones having fplit and mouldered away in the walls, and the foundations failed in many places. Phil. Tranf. N° 218. p. 150. See Gypsum.

GYPSINUM metallum, in the natural hiftory of the antients, a name ufed for the common lapis fpeailaris, of which they often made windows as we do of glafs. It was by fome called cyprinum fmtallum,becaufc frequently found in Cyprus. Hill's Theophraft. p. 142.

GYPSOCHI, artifts who work in plaifter. See the article Para dig ram ma tice.

GYPSOPHYTON, in botany, a name given by fome au- thors to the faxifraga antiquornm y or faxifrage of the an- tients. Chabrati^ p. 210.

12 R GYPSUM