Page:Cyclopaedia, Chambers - Supplement, Volume 2.djvu/119

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NEL

N E P

3 P . Tire part of the fkin which appears Hack in r.egroes',_\s the corpus rdim'are cutis, and external lamella of the epidermis : all other parts are of the fame colour in them with thofe of other people, except the fibres which pafs between thofe two parts. 4°. The colour of negroes does not proceed from any black humour, or fluid parts contained in their ikins j there being none fuch in any part of their bodies, more than iii white peo-

-°. The epidermis, efpecially its external lamella, is divided into two parts by its pores and fcales, two hundred times Ids than the particles of bodies on which their colours depend. Tins is founded on LeuWcnhoek's obfervation that a portion of the epidermis no bigger than what can be difcerned by the naked eye, is divided into iz^ooo pores, and thefe pores mull divide fuch a portion of the (kin into as many particles. But the particles of bodies on which their colours depend, are, by Sir Ifaac Newton's Optics, Lib. i. P. 3. Prop. 7. 600 times Jels than thefe which can be difcerned by the naked eye. Therefore the particles of the fkin rauft be about 200 times lefs than thefe ; fmce ^ f~ . = 2087 • It may alfo be obferved that fuch a fmall portion of the epidermis is divifible into 250 -fcales, which mult encrcafe the number of its parts. 6°. From thefe proportions, and from Sir Ifaac Newton's theory of light and colours, the doctor thinks he may conclude, that the proximate caufe of the colour of negroes is threefold ; viz. The opacity of their fkin, proceeding from the thicknefs and denfity of its texture, which obftructs the tranfmiffion of the rays of light, from the white and red parts under the fkin, together with its greater refractive power, which abforbs thefe rays; and the fmallnefs of the particles of this fkin, which hinders it from reflecting any light.

7 , The influence of the fun, in hot countries, and the man- ner of life of their inhabitants, are the remote caufes of the co- lour of negroes, Indians, &c. And the ways of living in ufe iimongft moil nations of white people, make their colours whiter than they were originally, or would be naturally. Jn fupport of this propofition, the doctor dbferves, that the fkin is deprived of its white colour, by the force and influence of the fun, four ways. lit. By being rendered opaque, from, a diflipation of its more aqueous, and pellucid juices. 2dly. By a concretion of its veflels and glandules, from this diffipa- tiori. of their aqueous contents^ which renders the fkin both thicker and denfer, or more callous and rigid. 3dly. By a new accretion of many new membranes, which render it thick and opaque. 4±hly. By encreafing thofe parts or principles, in the tompofttion of the epidermis, which have the greateft refrac- tive power j as the terreftrial and fixed faline; but efpecially the tenaceous Sulphureous, which refract and abforb light more ftrongly than any other fubitances ; while the more tranfparcnt and pellucid principles, as the aqueous, fpirituous, and volatile faline, are evaporated by the heat, which caufes the other more fixed principles to be accumulated ; and thefe particles being likewife more comminuted by the fun, will, on this account, be black; as happens to nil when well boiled. Thefe caufes s with thofe mft-rnehtioned, may, the doctor thinks, by con- fpiring make the fkin quite black ; efpecially if we add another effect of the fun's power, a peculiar necrofis of the epidermis, becafioned by the f rcible vibrations, contractions, and exfic- cations of its fibres by the fun beams which caufe it to turn black, as thefe, or other parts do, by the heat of an inflamma- tion, or a fever, in gangrenes, black tongues, &c. We cannot pretend to follow the author in all the detail of his obfervations on this fubject, nor of his anfwer to a material objection already mentioned from Mr. Boyle, that the fun cannot be the caufe of the colour efinegroes, hecaufe feveral na- tions, in the fame latitude with thofe negroes, are not made black by it He feems to think the heat of Africa greater than that of other parts of the world. Whether it be fo, or not, is we doubt, not eafy to determine ; but it would be a ftrong confirmation of his doctrine, if we could fee any people, ori- ginally white, become black and woolly by tranfplantation, or vice vcrfa. Negro, in zoology, the name of a large bird approaching to the crane kind, and more ufually known among authors by its Brafilian mrfte jztbiru. See Jabirv. NELANJENDMi in natural hiftory, the name of a curious and peculiar foffile fub fiance found in" the Eaft-Indies. It has much the appearance of fome of our lteel-grained lead ores, and is very ponderous, but it does not contain any lead ; in this it approaches to the nature of that fubftance common in Europe, arid called blende, or mock lead ; but this laft is fo- liated, and relemhles the plated lead ores, whereas this refembles the dole ground ores. It is found in the beds of rivers in ma- ny places • they calcine it, and, reducing it to powder, mix it With the juice of herbs, and ufe it in ulcers. NKLLA corvindsm, in natural hiftory, a name given by the peo- ple of the Eaft-Indies to a very hard ftone which they ufe as we do emery.

It is of a talcky nature, being compofed of flaky fpangles, and a coarfcr matter intermixed. They dig it at the foot of fome mountains, and m fome other places, "it lies fo near the fur- face that the nce-ficlds abound with it ; and it is feen on ftir- nn* the ground, ft i s always found in modules, or detached ol'ppl. Vol. II.

niafles, and is ufually of a fort of iron colour, though fubjeel to fome variations, Jt is ufed by the common people to fcowef arms, and other iron works; and by ■ the lapidaries, among them, to polifh rubies, and other itoncs. For this laft pur- pofe they grind it with flick lack, and make it into a fort of ce- ment, with which they daub over the face of the polifhing ma- chine. NELLON, in botany, a name given by fome to rice* It is art Indian word, and properly fignifies the grain of rice taken off from the flalks, but covered with its proper pellicle. The firffc operation to be performed upon this, is the beating it with large Hones, of other more manageable tools, till this fkin flies off. Then it is to be dried in the fun, and, after that beat a fecond time, to get off its thin, internal, redifli coat : when this is done, it is in a irate to be ufed, and it is then only that the In- dians call it arift, the word from which we formed our word rice. Obfervations fur Its Coutumes de 1* Afle. NELUMBO, in botany, the name of a genus of plants, ufually confounded with the nymphsea.

The characters of the nelumlo are thefe : The flower is like that of the nymphasa, but the fruit wholly different,, not only in fhapc, but in ftructure, being not divided into feveral cells, but having the feeds placed irregularly, at diftances from one an- other in it

There is only one known fpecies of this genus, which is the nelumbo of the Ceylonefe, called by others the Indian nymphaa, zndfaba Mgyptiaca, the /Egyptian bean. Town. Inft. p. 261. NENUPHAR. The antient writers on the materia medica, have all mentioned a peculiar fpecies of this plant, undef the name of ?ienupbar indicum. The roots of this they call fel, and Avifenna fays, that they have the fame virtues with the mandrake. Fel is alfo the name Of another very different medicine ufed in thofe times ; a fruit of a climbing plant, of the fize and figure of a cucumber, as to ftalks and leaves, but bearing for fruit this fel, which was a fort of nut of the fize of a pittachea nut, and covered with a thick fhell. This fel was of the nature of the bel and fel, two other fruits of a like fort, all heating and drying. Thefe were qualities altogether oppofite to thofe of the mandrake ; and the fynony- motts ufe of the word fel for thefe two things not having been obferved, the author is accufed of contradicting himfelf in dif- ferent parts of his works, when, in reality, he is treating of contrary things, tho' unluckily called by the fame name; the one a cold root, the other a hot fruit. Nenuphar, in botany, is alfo a name ufed by fome authors for

the water-lilly. Ger. Emac. Ind. 2. NENUFARINI, a name given by the adepts to a kind of ima- ginary fpirits which they fuppofe to inhabit the air, and to di- rect and govern many things on earth. NEOCORI, Ncoxofot, among the antients, perfons whofe bufiriefs it was to take care of temples, and other confecrated places. They were otherwife called aditui. Pitifc. in voc. Sec the ar> ticle^Drruus. NECENIA, Neowa, in antiquity, a feftival celebrated in honour of Bacchus, when the new wine was firft tailed. Pott, Ar- chajoh T* 1. p. 416. NEOMENIA, NeopwvKB, in antiquity. SeeNuMENiA. NEOPTOLEMIA, Vtwjfo>*xy.nx> in antiquity, a feftival celebrated by theDelphians with much pomp and fplendor, in memory of Neoptolemus, the fon of Achilles, who was (lain in an attempt to fack Apollo's temple, which he undertook in revenge of his father's death, to which that god was acceffary. Pet. Archreol, Graec T. r. p. 416. NEOTTIA j in botany, the name given by Linnzeus to the plant called by Tournefort and others nidus avis, and by Ruppius corallorhiza. Linmei Gen. PI. p. 434. See Nidus avis. NEPA, a word ufed by naturalifts fometimes to exprefs a crab, fometimes for a fcorpim, and fometimes for a plant, called by the botanifts gemfia Spartium. NEPENTHE^, in botany, the name of a genus of plants, the characters of which are thefe : the perianthium is divided into four round ifh fegments ; there are no petals, and fcarce any ltamina ; but four anthers are affixed to the ftylus near its top ; thepiftil has an extremely {lender germen ; theltyle is pointed, and of the length of the cup ; and the ftigma is obtufe ; the fruit is an oblong, columnar, truncated capfule, faintly quadran- gular, confuting of four cells, and ma.eup of four valves. The feeds are numerous, pointed, and of a chaffy ftructure, and are fhorter than the capfule. Linnat Gen. PL p. 437. NEPETA, catmint, in medicine. See Catmint. NEPHALIA, among the Greeks, a feftival called the feaft of fo- ber men, at which the Athenians offered to the fun and moon, to Aurora aud Venus, a drink made of water and honey. They burnt all forts of wood on the occafion, except the vine and fig-tree. Danet. in voc. NEpHRITICUM /#«»/», or Nephritic wood. See Trans- mutation of colours. NEPHRITIS, [Cycl.) in medicine, is ufed for an inflammatory affection of the kidneySj owing its origin to a ftagnatory con- geltion of blood in them, which nature feems to have intended to direct to the internal, hemorrhoidal veflels, thence to be difcharged to eafe her of the load of a plethora. The Ample nephritis is thus carefully to be diitinguifhed from C c the