Page:Cyclopaedia, Chambers - Supplement, Volume 2.djvu/178

 OYS

O Y S

OXYRYNCHUS, in zoology, the name of a fifh of the trut- taceous kind, called by feme hauth, and ouihi. It is caught frequently in the Eiigllfh and other fcas, and is frequently car- ried to market in Holland among the whitings. It is very- much of the fhape and figure of the trout, but a little flatter, and is covered with large white fcales. The back is of a fome- what dufky colour, and the lines on the fides a little bent near their origin. The tail is forked ; but the mark by which it is moft readily diflinguifhed from all other fifh of this genus, is the figure of its Grout, or upper jaw, which runs out beyond the under, and goes oft* rounding and tapering to a point, making in the whole a fort of conic figure. The head is fomewbat tranfparcnt. It has no teeth, but a confiderably rough tongue. Aldrovand. de Pile. 1. J.c. 24. OXYS, in botanv, the name by which authors call wood-forrel. The chaructersof this genus of plants are thefe: the flower confiftsof one leaf formed into a bell-, and wide open at the mouth, where it is alfo divided into feveral fegments. From the cup of the flower there rifes a piftil, which is fixed like a nail into the bottom of the flower, and ripens into an oblong membranaceous fruit, ufually divided into five cells, opening outward from the bafe to the apex,and full of fmall ieeds, which ufually fly out forcibly on the touching the feed-veflel, by means of the elasticity of fome of its parts. Town. Tnft. p. £9. The fpecies of 6xp enumerated by Mr.Tournefort, are thefe : 1. The common white flowered one, called by authors trifo- liuvi acetofum, and allelvjajlore alio. 2. The purple flowered kind. 3. The blue flowered kind. 4. The common yellow one. 5. The upright American yellow flowered one. 6. The fibrofe rooted American one, with red flowers. 7. The yel- low fhrubby American wood-forrel, having the appearance of the ftinking trefoil. 8. The fcaly rooted purple xvood-forrel of Virginia. 9. The bulb ofe- rooted African exys, with roundiih leaves and with purple ftalks and large purple flowers, jo. The bulbofe-rooted round-leaved African otys, with green ftalks and large purple flowers. 1 1. The ./Ethiopian bulbofe- rooted exys, with heart fafnioned leaves, and large purplifh white flowers. See Tab. 1. of Botany, Clafs 1, The feveral fpecies of this plant are ufually diftinguiftiable even when they are not in flower, by their having their leaves grow- ing regularly three at the top of every ftalk; and being each ufually of the figure of a heart at cards, and thefe are gene- rally of an agreeably acid flavour. See Sorrel, OXYSAh-ditipboreticum, the name of a compound medicine greatly recommended by feveral authors, and invented by An- gel us Sala. The manner of preparing it is this : take fine fait of carduus benedictus, put it into an earthen pot, and pour upon it gradually fome flrong wine-vinegar, or fpirit of fugar j continue to pour this on till the ebullition ceafes and an agree- able frnell arifes, and the matter has an agreeable tho' fome- what acid tafte ; let all the humidity from this mixture be evaporated over a gentle heat, arid after this, let all the fait be ! again diflblved in water, and fet in digeftion in balneo marine for eight dais : a liquor of a beautiful and pellucid colour is there produced, which, when poured carefully ofF into ano- ther veffel, is to be again evaporated to a drynefs with a very gentle heat, and the remaining matter, which is the fait, is to be collected together, and kept in a phial carefully ftopt ; for it is fubject to run, if left to the accefs of the air, like the common alcali falts. OXYSCH/ENOS, in the materia medica, the name of thejun- cus a cuius capitutU jo'gl'i j or hard pricking large fea-rvjh. Dale, Pharm. p. 258. See Juncus. OXYTOCHA, in medicine, a term ufed by many authors to

exprefs fuch medicines as are given to promote delivery. OXYTRIPHYLLUM, in botany, a name ufed by fomeauthors for the trtfolium bitum'wofum, or /linking trefoil. Chair ecus p. 1 10. OYSTER, orOi ste r ,cjlrea,m zoology. Seethe art'icleOsT r. e a. The oijler affords the curious in microfcopic obfervations a very pleafing entertainment. In the clear liquor many little round living animalcules have been found, whofe bodies being conjoined, form fpherical figures, with tails not changing their place otherwii'e than by finking to the bottom, as being heavier than the fluid; thefe have been feen frequently fepa- rating, and then coming together again. In other oifters, ani- malcules of the fame kind were found, not conjoined, but fwimming by one another, whence they fecmed in a more perfect ftate, and were judged by Mr. Lewenhoek, to be the animalcules in the row or femen of the oifler. A female ci/ler being opened, incr dible multitudes of fmall embryo oijlers were feen, covered with little fhells, perfectly tranfparent, and fwimming along flowly in the liquor : and in another female, the young ones were found of a browner colour, and without any appearance of life or motion. Monfieur Job'ot alfo kept the water running from oi/lers three •Jays, and it appeared full of young ei/iers fwimming about nimbly in it; thefe increafed in fize daily, but a mixture of wine, or the vapour of vinegar, killed them, In the month of Auguft alters are fuppofed to breed, became young ones are then found in them, Mr. Lewenhoek, on the fourth of Auguft, opened an cijler, and took out of it a prodi- gious number of minute oijlers, all alive, and fwimming nim- bly about in the liquor, by means of certain exceeding fmall organs, extending a little way beyond their fhells j and thefe

he calls their beards. In thefe little cijlen he could discover" the joinings of the fhells, and perceived that there were fome dead ones, with their fhells gaping. 1 hefe, tho' fo extremely minute, are feen to be as like the large ei/iers In form, as one egg is to another.

As to the fize of them, lie computes, that a hundred and twenty of them in a row would extend an inch; and confe- quently, that a globular body, whofe diameter is an inch, would, if they were alfo round, be equal to a million, feven hundred and twenty-eight thoufand of them. He reckons three or four thoufand are in one eijler, and found many of the embryo oijlers among the beards; feme fattened thereto by flender filaments, and others lying Icofe : he likewife found animalcu'es in the liquor five hundred time's lefs than the em- bryo oijlers. Lewenhoek Arcan. Mat. T. 4. p. 5 1 3. It is not very uncommon to fee on oijler fhells, when in a dark place, a Alining matter or bluifh light, like a flame of bnmitone, which flicks to the fingers when touched, and con- tinues mining and giving light for a confiderable time, tho* without any fenfible heat. This mining matter being exa- mined with a microfcopc, was found to confift of three forts of animalcules : the firft, whitifh, and having twenty- four or twenty-five legs on a fide, forked, a black fpeck on one part of the head, the back like an eel with the Ac in ftripped off. The fecond fort, red, refemblinff the common glow-worm, with folds on its back, but legs like the former; a nofe like a dog's, and one eye in the head. The third fort, fpeckled, with a head like a foal, with many tufts of whitifh hairs on the fides of it. Some much larger and greyifti might be feen, having great heads, two horns like a fnail's, and fix; or eight whitifh feet; but thefe did notfeem to Aline. Philof. Tranfact. N. 279.

As the bodies of lobfters, and fome other forts of fifh, tainted flefti, rotten wood, and other fubftances., are fomctimes found to fliine with a light like that on etjier fhells, may it not very probably proceed from the fame caufe ? Some alfo have gone fo far as to imagine the willow-wifp, fo common in fenny countries, to be only a collection of flying infects, which emit light from fome part of their body, as the glow-worm and lantron-fly do ; and the place, motion, and fome other cir- cumftances of that lambent flame, as it is called, feem, indeed, not a little to favour that conjecture. Baker's Microfcope, p. 241.

i^/f-OysTERs. The greater! bed of f affile- oijlers any where known of, is that near Reading, in Berkshire. They have the en- tire Aiape, figure, and are of the fame fubftance with the re- cent oijler fhells, and yet muff, have Iain there for a long time, the oldeft hiftories that mention the place giving an account of them. They are extended over no fmaller a fpace than fix acres of ground, and juft above them there is a large ftratum of a greenifli loam, called by fome writers a green earth, and by others a green fand. It is compofed of a crum- bly marie, and a very large portion of fand. Under them there is a thick ftratum of chalk, They all lie in a level bed, and as the fea comes no where near this part of the kingdom, it Aiould fcem, that the deluge only could give place to them here. It has been idly imagined by fome, that the Roman foldiers once quartered there, threw away thefe ftiells from the oifters they fed on in vaft quantities, but this is anfwered by obferving, that the ftrata above the fhells are natural, and have never been dug thro' till the time of finding the fhells. The oijler fhells and green earth together, make a flratum of about two foot thick ; and over this, a much thicker ftratum, of a bluifli and very brittle clay, but this has never been dug through, except where we find the fiiells. The people call this piercy-clay, and fay it is fit for no ufe. This bed of clay is about a yard deep, and above it is a ftratum of fuller's earth, about two foot and an half deep. It is of a very good kind, and is ufed by the clothiers. Over this there lies a ftratum of a fine white fand, unmixed either with the clay or fuller's earth : this is near feven foot deep, and above this there is a ftratum of a ftift* red clay, of which they make tilts in the place. This is covered with a little vegetable mould, and the depth of this ftratum of tile-clay cannot be afcertained, be- caufe of the unevennefs of the hill.

Thefe sifters are fometimes found whole, but more ufually in fingle Aiells. When they are in pars, there is ufually fome of the green fand found within them: they feldom ftick very faft together, fo that unlefs very carefully taken up, it is not eafy to get them in pairs. Phil. Tranf.N. 261, p. 484.

Oyster-JSW/j. Thefe are an alcali of a more powerful kind than is commonly fuppofed, and probably are in reality much bet- ter medicines than many of the more coftly and pompous alka- lies of the fame clafs. The proof of alkalies is in their folution byacidfpirits; and Mr. Homberg found, that they diflblved much more eafily in the acids of nitre and fea-falt, than pearls, coral and the reft ; which he fuppofes owing to their containing in the body of the fhell a confiderable portion of fal-falfus, which is eafily perceived upon the tongue, and which keeps the whole fubftance of the fhell in a fort of half diflblved ftate. Thefe ftiells are found to produce very great effects on the fto- mach, when injured by acid humour?; and Mr. Homberg is of opinion, that this their eafinefs of folution is one great rea- fon of their good effects, and that the quantity of fal-falfus

which