Page:Cyclopaedia, Chambers - Supplement, Volume 2.djvu/491

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trie, leaves, will by this means putrefy, but they require a different time for this, fome will be fmifhed in a monih, and others will require two months, or longer, according to the hardnefs of the parenchyma of them. When they have been in a ftate of putrefa&ion fome time, the two mem- ' branes will begin to feparate, and the green part of the leaf ' to become fluid ; then the operation of clearing them is to

be performed. The leaf is then to be put upon a flat white

earthen -plate, and covered with clear water; and being gently fqueezed with the finger, the membranes will begin to open, and the green fubftance wiil come out at the edges ; the membranes mult be carefully taken off with a finger, and great caution muft be ufed in feparating them near the middle rib. When once there is an opening toward this Teparation, the whole membrane always follows eafily ; when both membranes are taken off, the Jkeleton is finifhed, and it is, to be warned clean with water, and then preferved be- tween the leaves of a book.

The fruits are diverted of their pulp, and made into Jkele- tms in a different manner. Take, for inftance, a fine large r pear that is foft, and not irrongj let it be nicely pared without fqueezing it, and without hurting either the crown or the ftalk ; then put it into a pot of rain-water, cover it, fet it over the fire, and let it boil gently till it is perfectly foft, then take it out, and lay it in a difti filled with cofd water ; then hold it bv the ftalk with one hand, and with the other hand rub off as much of the pulp as you can with the finger and thumb, beginning a., the ftalk, and rubbing it regularly towards the crown. The fibres are molt tender toward the extremities, and are theieiore to be treated with great care 'there. When the pulp is thus cleared pretty "well off, the point of a fine penknife may be of ufe to pick " away the pulp flicking to the core. In order to fee how the i operation advances, the foul water muft be thrown away ' from time to time* and clean poured on in its place. When the pulp is in this manner perfectly feparated, the clean fie- leton is to be preferved in fpirit of wine. Skeletons of roots which have woody fibres, fuch as turneps, and the like, muft be made by boiling the root without peeling it till it be foft, that the p.ilp may be fqueezed away by the fingers, in the fame manner, in a difti of water. Many kinds of roots are thus made into elegant Jkelet6/:s., and the fame method fucceeds with the barks of feveral kinds of trees ; which when thus treated, afford extremely elegant views of their conftituent fibres. Philofi Tranf, N°4i6* SKEW, or Skill facets, among jewellers. See Facets. SKIN [Cycl.) — The cuticle, or {tyrf-fkin ■ of the human bodv, is remarkabje for its fcaies, and for its pores. Its fcales are wholly a mlcrofcopical difeovery, f° r being fo very minute, ihat two hundred of them may be covered with a grain of fand, they never could have been difcovered by the naked feye. Thefe are placed on our Jkln as on fifties, that is three deep, or each fcale fo far covered by two others, that only a third part of it appears ; and thefe lying in this manner over one another, feem the rcafon of the Jkln\ appcarin: white; for about the mouth and lips, where they only ju: meet together, and do not fold over, the blood-veflels are feen through, and the parts appear red. The perfpirabL matter is fuppofed to iiliie from between thefe fcaies, which lie over the pores, or excretory veffels, through which the watery and oily matters perfpirc ; and thefe may find vent in! a hundred places round the edges of each fcale: fo that if a! grain of fand can cover two hundred of thefe fcaies, it may cover twenty thoufand places through which perforation I may iflhe forth.

A piece of the Jkln taken from between the fingers; from the forehead, neck, arms, or any other foft part of the body, which is not hairy, ferves to fhew thefe fcaies ; for where the fkin is become hard and callous, they are faftened con- fufedly together. They are generally compofed of five fides, and may be feen very diftinclly if fcraped off with a pen- knife, and applied to the microfcope in a drop of water. Baker's Microfcope, p. 169.

Every part of thefiin of the human body is alfo full of ex- cretory ducts, or pores, which continually emit the fuper- fluous humours from among, the mafs of the circulating fluid. In order to view thefe pores, cut a Mice of the upper Jkln with a {harp razor, as things pofHblej then immediately cut alfo a fecond flice from the fame place, which apply to the microfcope ; and in a piece of this, not larger than what a grain of fand can cover, there may be difcovered innumera- ble pores as plainly, as little holes pricked in paper by a fin< needle may be perceived, when it is held up againft the fun. The fcaies of the upper Jkln prevent any diftinft view of the pores, unlefs they are thus cut off firft, or elfe (craped away with a penknife ; but if a piece of the Jkln between the ringers, or in the palm of the hand, be fo prepared, and then examined, the light will be feen very beautifully through its pores. Lewenboek, Arcan. Nat. Tom. 3. p. 413. Mr. Lewenhoek has attempted to give fome flight notion of the number of the pores in the human body : he fuppofes that there are a hundred and twenty fuch pores in a line bne tenth of an inch long; however, to keep within com- pafs, he reckons only a hundred; an inch in length will then Suppl. Vol. II.

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contain a thoufand in a row, and a foot twelve thoufarid; According to this computation, a foot fquare muft have in it a hundred and forty four- millions; and fuppnfmg the fuperfi- ciesof a moderate fized man to be fourteen feet fquare, there will be in his fkin two thoufand and fixteen millions of pores.. Dr. Grew has obferved that the pores, through which we pcrfpire, are more remarkably diftinguifhable in the hands and feet; for if the hands be well wafhed with foap, and ex- amined with but an indifferent giafs in the palm, or upon the ends and firft joints of the thumb and finger, thefe will he found innumerable little ridges parallel to" each other, and. of equal bignefs and diftance; and upon thefe ridges the pores may be difcovered by a very good eye, even without a glafs, lying in rows, but viewed through a good glafs, every pore feems like a little fountain, with the fweat ftand- ing therein as clear as rock water ; and this, when wiped away, will be found to be immediately renewed again. Probably fleas, gnats, and other infe&s, which feed on our .blood and humours, make no new holes, but prey upon us through thefe pores, Philof. Tranf. N 159. Skin, in commerce. The Indians in Carolina and Virginia drefs buck and doe-Jkins in this manner: the felt being taken off they ftrain them with lines, or otherwife, much like the clothiers racks, in order only to dry them: When' the hunting time is over the wemen drefs the Jklrisi by put- ting thc-m in a pond, or hole of water, to (oak them w^Il ; then with an old knife, fixed in a cleft ftick; they force off

the hairwhilft they remain wet. This done, they put them nto

a kettle, or earthen-pot, and a proportion of deers brair. j dried and preferved for this puipofe, is put in along with them ; this vefTel is fet on the fire till they are more than blood-warm, which will make them lather and fcour clean ; after this, with fmall ftirks, they wreft and twift each _/£/'*, as long as they find any wet to drop from them, k-tting them remain fo wrefted for fome hours, and then' they untwift and ftrt-tch each of them in a fort of rack, fo that every part is extended; and as the Jkln dries they take a dull hatchet, tor fome fuch inftrument, and rub them werf ovtr to force all the water and greafc out of them, till they become perfectly dry, and then, their work is done.

In this, manner one wuman (for the rrien never employ them- felves in this work) will drefs eight or ten Jkins- m a day, that is, begin and finifh them*. Phil. Trahf. N- 194. SKINK, Jeiiiciis, in zoology, &c. See Scincus. SKINUS, trxwlt, a name given by the antient naturalifts to the lentifk-tree, and alfo to a peculiar fpecies of the fquill, or fcilla; .which was- not naufeous and emetic as the common, fquill, hut efculent and pleafant to the taffe. The generality of writers, even among the antlents them- fclves, have not obferved the fvnonymous ufe of this word, and tranferibing at random paffages from one another, have confounded the names of the lentift-tree and of this efculent fquill, and related of the one what the original writer laid of the other. Hence many of the abfiirdities which we find in the works of fome, but which are by no means to be at- tributed to all of them.

Pericles was called, by way of derifioir among the comic writers of his lime, Skinorephahts, this term expreffing his having a head like the Jkinos, muft be wholly unintelligible to thofe, who fuppofed it meant as the name of the lentifk- tree ; but when it was underftood to be me;mt of the fquill, the fatire was plain, as a large and mifshapen head, fuch as that of Pericles was, could not eafdy be better likened to' any thing, than to the irregular, large, and oblong bulbous root of this plant.

Epicharmus, in Athenseus, names the Jklnos as a kind of eatable fquill ; and Theophraftus exprefsly fays, that the roots of all fquills were not eatable, but that they only eat thofe of the Jklnos, or, as others called it, the E-ptmmedian Jquill, a fort of that plant fo called, after the name of one Kpimenides, who firft brought it into ufe. The after-writ- ers run into great errors about this word,- fome of them franflating Theophraftus's epithet into a fubftantive, and di- ftinguifhing the Epimenedium from the fcilla. Pliny, in particular, is guilty of this error. This is the peculiar fpe- cies of fquill^ which the Athenians afterwards diftinguifhed from the common kind, by the name Jklnus. Theopompus mentions the Jklnus as an efculent kind of fquill ; and, in general, the word oftener occurs as the name of the fquill, than as the name of the lentifk-tree.

Theophraftus mentions the infert'mg an efculent root on' the Jkinos, or fkilla, giving the choice of either of thofe roots, and fays that it will thrive much better on this, than in the earth alone; the tranflators have rendered this the lentifk : but where is the probability of this excellent botanift's ad- vifmg the grafting an efculent foot upon a tree, or giving a tree, and a common bulbous plant, as indifferent to the choice which was to be ufed ? Pliny, lib. 23. cap. 5. TTw- fhrajlus, lib. 5. c. 7. See Lentiscus. SKIPP£R,anEnglifh nameforthecommon gar-frm. See Acus. SKIRRET, fijarum, in botany, &c. See Sisarum.

The Jklrrety though one of the moft wholefome andnouriuV ing of all the efculent roots, is very little cultivated with us,

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