S I L
texture* and very rough and dufty furface. It adheres firmly to the tongue, is fomewhat foft to the touch, crumbles eafily to pieces between the fingers, and ftains the hands very much. It melts freely in the mouth, and has a ftrongly aftringent tafte. It burns to a much paler colour, and makes' no effervefcence with aqua fortis. Thefe are the cha- racters by which this is diftinguifhed from all the other red earths. It is dug in many parts of England, and is fent to London in great quantities. Hill's Hift. of Foil", p. 57.
Sil aiticum is the purple ochre, called of later times almagra. See the articcle Almagra.
Sil marmorofum is alio a fubftance m fome degree known in the world at this time. It fometimes fulls into the hands of our painters who call it Indian ftone red, but it has many Other valuable qualities extremely worth enquiring into. It is the hardeft and drieft of all the ochres, and while in the ftratum appears abfolutely ftony, forming thin, flat, regular ftrata and is fo hard that it is not to be dug without the pick-ax; it is alfo of an obfcurely and irregular laminated ftrucrure, and naturally breaks into flat pieces. It is of a fine purplifh red, and very heavy, and contains a multitude of fragments of a fine lead ore which are bright and bluifh, and make a very pretty appearance, and befide thefe has al- ways among it a fmall quantity of pure native cinnabar ; -both thefe fubftances are fo nicely mixed with it, that it is fcarce poflible to break off a piece of an inch fquare from any part of the ftrata, that has not more or lefs of both in it. It is of a dufty furface, and rough to the touch, and adheres very firmly to the tongue, and ftalns the hands. It is of a very auftere and aftringent tafte, and makes no effervefcence with acids. There are considerable ftrata of it on the bor- ders of China, and it is much ufed as a paint in the Eaft- Indies. There is fome of it at times brought over to us, but not enough to make it a regularly marketable commo- dity. Befide its ufe as a painr, it is worth enquiring into an account of the cinnabar it contains ; three ounces of it hav- I ing yielded, on trial, two drams and a fcruple of pure quick- filver. Hill's Hift. of Foff. p. 62.
SILACH, a word ufed by medical authors for a diforder of the eye-lid, conftfting in a preternatural thicknefs of it, or a fwelling without inflammation.
SILATUM, a word ufed by the antient Romans to exprefs a morning's draught of wine. This was ufually of a wine medicated with the plant fili, or fefeli, and thence' had its name. It has always been the cuftom to medicate the morn- ing draughts of any ftrong liquor ; we do it with worm- wood, or the common bitter tin&ure, the Indians with ginger.
SILAUM, in botany, a name ufed by fome authors for the faxifraga pratenfs, or common meadow-faxifrage. J. Bauhin. Vol. 3. p. 170.
SILENE, in botany, the name of a genus of plants, the cha- racters of which are thefe. The perianthium is oblong, fmooth, and clavatcd, and confifts of one leaf, divided into five fegments at the edge. The flower confifts of five petals : the ungues of thefe are as long as the tube of the cup, and their extremities form a limb, which lies flat and ex- panded : the apices of all the petals are obtufe and marginated. The nectarium is compofed of certain denticuli, two of which are inferted near the bafe of every petal. The fta- mina are ten fubulated filaments, inferted into the ungues of the flower. The anthers are oblong. The germen of the piftil is cylindric. The ftyles are either three or five, and are of the length of the ftamina, or fomewhat more. The ftigmata are always bent againft the fun. The fruit is the germen enlarged, and divided into as many cells as there were ftyles : thefe contain numerous kidney-fhaped feeds. Dillcnius, in the Hortus Elthamenfis, has defcribed thefe plants under the name vifcago. Linnai Gen. Plant, p. 107. Dillen. Hort. Elth. p. 309.
SILER, in botany, a name given by the Latin writers of the later ages to the plant called by others fefeli, an umbellife- rous herb, growing in mountainous places. The antient Roman authors, however, mean a very different thing by the word filer, a fhrub growing in watery places, and having twigs very ducfile and tough, and fit for bafket- work, or any other ufe of that kind. The poets have often mentioned it, and always with the epithets of molle and len- tarn, foft and tough.
Nothing can be more obvious, than that the filer of the later authors is a plant wholly different from this ; and it is very properly that fome have denominated the umbelliferous plant filer montanum, to diftinguifli it from the ihmb-filer, which only grows about waters.
Some of the old fcholiafts and interpreters of the Roman authors have told us that the filer, mentioned by them, is the cyperus ; but this muft be a miftake. For though this plant grows in watery places, and has confiderable tough ftalks j yet it is not a fhrub, but an herbaceous plant, and is remarkably harfh, and of all plants leaft deferves the epi- thet molle, which the antients beftowed on their filer. Some have fuppofed it to be the willow ; but this cannot be true : for the willow and filer are continually named toge- ther, by the fame authors, as different plants. The willow, Suppl. Vol. II.
S I L
alder and filer, being the three fhrubs generally mentioned' together, as the fhrubs that grow about tiie banks of rivers 3 the ofier is a kind of willow, very frequent at the fides of rivers, and has all the qualities attributed to the filer by the antients. It has been fuppofed by fome that this cannot be their filer, becaufe as it is a kind of willow, they would have called it by the common name, falix ; but our own example may plead againft this, for we know it to be of the willow-kind, yet we call it by another name: ofier is more different in found from willow, than filer from falix, and probably both one and the other fignify the fame plant. The error of confounding fo different a plant as the fefeli with this fhrub, arifes from the unhappy cuftom of abbrevi- ation, fo common among the old Greeks; inftead of fefeli they wrote the word fometimes only felt, and file, thence it was eafy for people, lefs acquainted with botanical diftinc- tions, to add an r at the end, to reduce the word,. which they did not know, to one that they did ; and thus grew filer as a name for fefeli. Hippocrates calls the fefeli fili} and Pliny both fili and fell. See the article Sili.
SILESIACA-f<77-<7. See the article Terr A-filefiaca.
SILEX, flint, in natural fnftory, the name of a genus of femi- pellucid ftones, the matter of which is a cryftal, debafed by an admixture of a peculiar and appropriated earth, which is of a blackifh grey ; always free from veins, but, according to the different quantity and difpofition of the earth in its compofition, fubje£t to clouds of a darker or paler colour, and naturally inverted with a thin whitifh cruft. Naturalifts, in general, have accounted various fpecies of flint, but erroneoufly ; nature has eftablifhed it into a genus of itfelf, and allowed no other fpecies than one, which is ever compofed of the fame matter, and differs only in the proportions of its admixture. When cryftalline matter is de- bafed by earths of other colours, or clouded and veined, it ceafes to htfiint, and becomes the pebble, the agate, or the onyx; and the not attending to this diftin&ion, has made many defcribe thefe varioufly-coloured bodies twice over : once under the name of cohured flints, and a fecond time under that of EngUfi agates, &c.
The characters of genuine fint are, that it is a ftone of an. extremely fine and even texture ; of a very uncertain furface, fometimes rough, fometimes fmooth ; of a colour always, in fome degree, between blackifh and whitifh, unlefs acciden- tally tinged, as all other foflils are fubjecr. to be j very rea- dily giving fire with fteel; not fermenting with acids. Hill's Hift. of Foflils, p. 508. See the article Flint.
SILI, in botany, a name given by the old Greeks to a plant called alfo fefeli. Hippocrates always calls this fili and file t and Pliny ufes the fame words as fome of its names. This however is not the only meaning of the word, for the epithet cyprium being added to it, it fignified a very different plant, namely, the ricinus ; and the letter r being added to the end, and the word written filer, it became the name of the ofier, as well as of the fefeli. This has occafioned great errors about the meaning of the antients, fome mifunder- ftanding them as fpeaking of the ofier, when they arede- fcribing the virtues of the fefeli.
SILICERNIUM, among the Romans, a funeral fupper, which is otherwife called exequium. Pitifc. in voc. See the article
EXEQUIUM.
SILIL1CON, in botany, a name given by fome of the old Latin writers to the carob-tree, ox fili qua dulcis. The Latins borrowed this name from the Greek xyloglycon, Zvbo'xvxw, the fweet, or fweet-fruitcd tree. Ifidore mifpels the word filili- con, and making it only filicon, fuppofes it to be a barbarous way of fpelling the word filiqua ; but the evident derivation of the genuine word from the Greek fhews his error, both as to the word itfelf, and the origin of it. The Latins called this tree fil'iqua, becaufe its fruit was in pods, and the Greeks ceratium, xe^lw, becaufe its pods were bent fo, as to refemble horns ; but the names xyloglycon, and Its derivative, fililicon, were wholly different from thefe. The fame Ifidore obferves, that the exprefled juice of the fruit of this filicon is the drug called acacia in the fhopsj but in this he is guilty of a very great error, the fruit of the filicon being efculent, and the acacia a very powerful aftrin- gent.
What has led him into this error, has been an obfervatton of the Gloffaries on Avifenna, and the other Arabian phy- ficians. Thefe authors have called by the fame name, cbarub 9 or iharnuh, both the carob, or fililicon, and the acacia, only diftinguifhing them by proper epithets. Ifidore found in their Gloffaries, that charnub was the fiUqua, or carob-tree, and that the juice of the pods of charnub was acacia ; he therefore not obferving that there were two charnubs, gave to the latter the properties of the former, and fo made the ftyptic and aftringent drug the juice of an efculent plant.
SILICULA, in botany, a name given by fome authors to feenugreek. Ger. Emac. Ind. 2.
SILIQUA, (Cycl.) in botany, the name of a genus of trees, the characters of which are thefe. The flower is of the apetalous kind, being compofed only of a number of fta- mina, which arife from the fegments of the cup, the middle of which is occupied by a piftil, which finally becomes a 2 N n n flatted
