Page:Cyclopaedia, Chambers - Supplement, Volume 2.djvu/484

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flatted pod of a flefhy fubftance, and containing fiat and roundifh feeds.

The fpecies of filiqua, enumerated by Mr. Tournefort, are thefe: i. The common filiqua, called the eatable filiqua, orcarouge. 2. The efculent ///?wfl with fborter pods. 3. The efculent filiqua with various pods. 4. The wild carouge, or not efculent filiqua. Tourn. Inft. p. 578.

Siliqua, xffd?io>j among the antients, the third part of an obolus, or, what comes to the fame, the fixth part of a fcruple. See the articles Obolus and Scruple, Cycl.

SiLiqi'A nahathaa. See Nabathjea filiqua.

SILIQUARIUS, among the Romans, an officer who exacted, or railed the toll filiqua. Pitifc. in voc.

SILIQUASTRUM* Judas-tree, in botany, the name of a genus of trees, the characters of which are thefe. The flower is of the papilionaceous kind ; the wings, however, ftand over the vexillum, and the carina is compofcd of two leaves. The piftil arifes from the cup, and is furrounded by ftamina ; this finally becomes a flat membranaceous pod, filled with feeds of a kidney-like form. To this it is to be added, that the leaves ftand alternately. See Tab. 1. of Botany, Clafs 22.

The fpecies of filiquajirum, enumerated by Mr. Tournefort, are thefe: 1. The common filiquajirum, or Judas-tree. 2. The white-flowered filiquajirum. 3. The filiquajirum with large pods and pointed leaves. 4. The round-leaved Czn&da-filiquafirum. Tourn. Inft. p. 646.

Siliquastrum was ufed in the botanical writings of the antients for the name of a podded plant, growing wild in fome places of Italy, and in others cultivated for domeftic and medicinal ufes. Pliny, and many other of the antients, have mentioned this, but they have given fuch imperfect accounts of it, that they have led their followers into many errors about it. At this diftance of time, and with the few lights they have left us, it is not eafy to fay what this plant of the antients was ; but it may be a means of leading the reader out of many errors, to fay what it was not. Many have fuppofed it to be the xinx'tber caninum of Avi- fenna, and the bydropiper of Diofcorides ; but the name///- auajirum implying its having pods, is a fufficient refutation of its being this plant, which is the common perficaria, or biting arfmart.

Others have thought that the filiquajirum was the capficum. or Guinea-pepper, as we call it ; but however well this plant may agree with the name, as being podded, it can by no means be the plant, fince Pliny defcribes it as common in Italy, and growing wild, which it is very certain that this plant never did.

Many have fuppofed it to be the plant we call piper 'iti's, or dittander; but though Pliny has called this plant plper'ttis, from its hot tafte of pepper, yet he plainly {hews that it was not our dittander : for he afterwards defcribes that as another fort, faying, that there is another broad-leaved kind, which approached to the nature of iberis, but that the large leaves diftinguifhed it: this is plainly enough our lepidimn, or dittander ; and therefore the other filiquajirum-, originally and properly fo called, cannot be that plant. Julius Scaliger obferves, that there is a fhrub growing in Provence at this

■ time, called filiquajirum ; he fuppofes this to be the filiqua- jirum of Pliny : it has leaves refembling thofe of the olive, and fhort crooked pods. But we do not And any thing ei- ther in Pliny, or any other of the antients, to counte- nance the opinion of the filiquajirum being a fhrub.

Siliquastrum, in natural hiftory, the name given by Mr. Lhuyd, and others, to the bony palates of fifties, when found foflile. See the article Ichthyperia.

SILIQUATICUM, among the Romans, a cuftom or toll paid for merchandife. This the Greeks called ceratifmus. See the article Ceratismus.

SILK (Cycl.) — Raw filk, which is a fubftance of no remark- able fmell or tafte, yet contains a furprifing quantity of a volatile fait. Fifteen ounces of raw filk cut fmall, and put into a retort, when diflilled with a gentle fire, will yield two ounces and two drachms of a dry volatile fait ; whereas fif- teen ounces of hartfhorn, a fubftance ufually fuppofed to contain more volatile fait than any other fubftance, except fal armoniac, yields only half an ounce and half a drachm : from the fame quantity of filk there may alfo be drawn three ounces and an half of volatile fpirit; whereas, from the like quantity of hartfhorn, the quantity of fpirit exceeds this, being four ounces and a half. But we are to confider, that there requires but a fmall proportion of volatile fait to be diffolved in phlegm, to make it what they call a volatile fpirit ; and that upon the whole there is no doubt, but that the filk contains greatly the larger portion of fait. The caput mortuum, from this quantity of hartfhorn, weighed nine ounces and two drachms ; whereas that from the filk was only five ounces and five drachms : whence it is plain, that the hartfhorn contains greatly more earth in the fame quan- tity, and confequently lefs active principles. It has generally been agreed, that the fpirit of hartfhorn is no other than a phlegm, impregnated with a volatile fait, and an extremely penetrating fulphur : this is proved by the fol- lowing experiment. If fpirit of wine be poured upon fpirit offal armunhtc, or fpirit of filk, there is immediately pro-

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duced a large quantity of a faline concretion ; and when the fpirit of filk is ufed, this concretion is manifeftly compofud of confiderably large and feparate granules of fait; whereas in cafe the fpirit of fal armoniac has been ufed, the concre- tion is perfectly fine, and of an even texture, and it is not eafy to fay, at firft fight, whether it be faline, or fulphu- reous : this is what has been called by authors affa Hchnontii, It is proved, however, to be wholly faline, on the adding water to it, fince that readily diffolves it. The fulphur which is contained in thefe volatile fpirits, manifefts itfelf fufficiently by its fmell.

The fpirit of raw filk rectified with fome effcntial oil, is rfie medicine commonly known by the name of guttes Anglicans, or Englifh drops. Mem. de l'Acad. Par. 1700. See the article Drops.

Silk being properly an animal fluid hardened' by the air, is ufually much mended or depraved in its nature and qualities, according to the nourishment the worm receives from a good or bad leaf; a great deal, therefore, depends on the good- nefs or badnefs of the fpring of the year, in the value of the filk produced. _ A warm fpring is beft, and it fhould be moderately moiff, not overmuch fo, becaufe too great a fall of rain is always found to rot the leaves. Southerly winds alfo are to be feared, becaufe they burft the worms \ and northerly ones, when ftrong, ufually fpoil the leaves. AH thefe being deftructive, either of the animals themfelves, or of their food, very juft prefages may be formed upon them of the produce of the enfuing year.

When thefe mifchiefs do not happen, but the fpring is fa- vourable, the people have little to do but to watch the feed- ing of the worms, and about Midfummer they are to begin to draw the filk from its cocoon, to fee what it yields, and, judge of its encreafe or fcarcity, and eftimate its goodnefs and perfections ; the principal of which are, that it proves clean, light, and ftrong.

Great ufe may be made of thefe obfervations, provided the management be good. It requires great care to hatch the eggs, and when hatched, there muft be a careful eye over the worms, even to the time of drawing off the filk. If the feafon foretels a fcarcity, the bufinefs of the prudent manager is to buy up all the old filk he can procure, and keep as much of the other as he can, to be employed in the beft fa- brics, that fo they may not be obliged to hazard all the good at the price of the worft : but when the feafon proves fa- vourable, they collect the new for the beft fabrics, and com- pare it with the old, to fee whether it be of a better quality, before they venture to determine their prices. The goodnefs of filk is beft diftinguifhed by its lightnefs, that being its moft eftential quality : this every one knows carries a very great profit with it, being bought by weight, and fold by meafure, at the firft hand, after the collectors. The Organcine filk is the beft of any made in the country of Piedmont, and two threads are equal in finenefs, that is in fmoothnefs, thicknefs, and length, for the thread of the firft: twift. For the fecond, it matters not whether the Angle thread be ftrong before the two are joined, unlefs to fee whether the firft twift prove well. It is necefiary that the filk be clean, and it is to be obferved, that the ftraw-colour- ed is generally the lighteft, and the white the heavieft of all. ' The fkains fhould be even, and all of an equality, which fhews that they were wrought together ; otherwife we may with juftie'e fufpect that it is refufefilk, and cannot he equally drawn out and fpun, for one thread will be fhortcr than the other, which is labour and lofs.

It will alfo be requifite to fearch the bale more than once, and take from out of the parcels a fkain to make an eflay ; for unlefs it be known by trial what one buys, there is the greateft danger of being cheated in this commodity. To make an eftimate, and know the lightnefs, fix the effay up- on one eighth of a portee, or hand of filk of a hundred and ten aunes or ells of Lyons in length, and fee what it makes of aunes by the eighth part. The fkain, which is of eighty threads, muft be multiplied by a hundred and ten aunes of Lyons, and from this number muft be deducted one eighth ; as for example, no by 80 makes 8800, the eighth part of which is 1 100 ; and this is the eighth part of a portee, or hand of filk. Now to calculate what thefe n 00 aunes weigh, which is the eighth part of a porte'e, or of no aunes of Lyons, it will be proper to take a fkain out of the parcels, which you take from out of the bale which you judge may contain, at leaft, 1 1 00 aunes, to make the one eighth part of a portee, which portee mull be divided on two robbings, half on each ; then fix the two bobbings on the center, or beam, and from thence pafs it through the comb hurdiiioir, viz. 550 from the two bobbings, will make 1 100, which will be one eighth part of what you defire to know. This done, you cut off your filk, and carry it to put on the hurdiflbir ; then weigh it, and multiply the weight by eight, it will weigh juft as' much as a portee of no aunes of Lyons, which is the ge- neral rule for calculating. When they draw the filk out by this means, one may learn to adjuft the weight. There are filks of Piedmont which are very light and clean, and are to be preferred before any on the fate : the portee of filk of the lighteft weighs near twenty four pennvweights,

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