Page:Cyclopaedia, Chambers - Volume 2.djvu/732

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Raw Silk, is that taken from the Cod, without Fire, and wound without boiling; fach is molt, if not all, that is brought into England from the J.evanr. In the French Silk-works, the greateit Part of this SiPk paffes for little better than a Kind of very fine Fleuret ; yer, when fpun, it makes a bright Thread, and ferves for the Manufacture of Stuffs of moderate Value, and Luflre : But the Raw Silks of the Le-vant, whence molt of ours come, are exceeding fine and beautiful. This Diffe- rence ariles hence, That in France the bell Cods are Ipun and wound in boiling Water, and only the Refufe made in- to Raw Silk : Whereas, in the Levant, there is no fuch thing as Spinning or Winding in the Fire ; but the Silks are all lent in Balls or Mafles, as they are drawn from off the Cods: So that they are only diltinguilhed by their Qua- lity of Fine, Middling, and Coarfe.

SoiVd Silk, is that boiled in Water, to facilitate the Spinning and Winding. This is thefineftof all the Silks ma- nufactured in France, and is feldom uled, but in the richell Stuffs, as Velvets, Taffeta's, Damasks, Brocades, &c. There is alio another Kind of Soiled Silk, which is pre- pared by boiling, to be milled ; and which cannot receive that Preparation, without being fir ft paffed through boiling Water. By the Laws of France, 'tis prohibited to mix Raw with SoiPd Silk ; both as fuch a Practice ipoils the Dy- ing, and as the raw Silk corrupts and cuts the boiled.

Tftfowed or Twijle.i Silks are fuch, as, befide their Spin- ning and Winding, have had their Milling or throwing This they have in a different Degree, as they are paffed oftener, or leldomer, over the Mill. Properly, however, thrcived, and are twilted feveral times. — Slack Silks are fuch as are not twilled, but are prepared, and died, forTapeltry, and other Works, with the Needle. See Throwster.
 * t&r&wed Silksiste'thoi'c wherein the Threads are pretty thick

F'afernSiLK : That particularly thus called, is not the Work of the Silk-Worms, but comes from a Plant that pro- duces it, in Pods, much like thole of the Cotton-Tree. The Matter this Pod contains is extremely white, fine, and mode- rately bright : It fpins eafily, and is made into a Kind of Silk, that enters the Manufacture of leveral Indian and Chinese Stuffs.

Spider-Silk. Within a few Years the Secret has been found in France, of procuring and preparing Silk of the Webs ofSpidersl and ufing it in leveral Manufactures. This Dif- covery is owing to M. Sen, in 1710. who publiflied a Differ- ration on the Subject $ whence what follows is extracted. See Spider-Wee.

Spiders are ufually diftinguifhed, either with regard to their Colour ; as, into Black, Brown, Yellow, White, ($c. or with regard to the Number, or Arrangement, of their Eyes ; fbme having 6, others 8, others 10. But with regard to' the Silk-Spider, M. Son reduces them all to two Kinds, thole with long Legs, and thofe with fhort ; which lair, arc thofe which furnifh the Raw Silk.

The Silk-Spider make a Silk, every whit as beauiful, flrong, and mining, as the Silk-worm: It fpins it out of tnejfcgf, around "which are Five Papilla:, or fmall Nip- ples, and behind thefe, two others j all mufculous, and fur- nifhed with Sphincters. Thele Nipples ferve, as ib many wire-drawing-irons, to form and mould a Liquor, which, when dried in the Air, after being drawn through them, is to be the Silk. Kach of thefe Nipples, M. Reaumur oblerves, confiits of a Number of Ieffer and infenfible ones ; which cne may be convinced of, by preffing a Spider's Belly between the Fingers, to oblige the Liquor to flow into the .Nipples; for by this Means, applying the Finger againft the Anus, feveral diffinct Threads will be drawn out through the leveral Perforations of the Nipples. The Threads are too fine to be told with any Certainty ; but M. Reaumur reckons, each larger Nipple may fend forth fix or feven. Hence we fee, how the Sliders make their Threads bigger, or fmaller : For as, before they begin to Spin, they always apply more or fewer of thele fix Nipples, againft the Body whence the Web is be- gun ; or as they apply each more or lefs ftrongly, fb as more or fewer of the infenfible Nipples come to take ; the Thread thus fpun, will be a Compound of more or fewer of the fingle Threads. Indeed, as the Threads come from the Amis, all joined together, they appear to be fingle; but M. Son has diftinguifhed one of the fingle ones to confift of 15 or 20 diftinct Threads.

The Threads are of two Kinds; The Firft is weak, and only ferves for that kind of Web wherewith they catch Flies. The Second is much Itronger, and ferves to wrap up their Eggs in ; which, by this means, are Iheltered from the Cold, as well as from Infects, which might otherways onaw and Ipoil them. Thele Threads they wind very ioofely round the Eggs, refembling the Cods or Bags of Silk-Worms, that have been prepared and loolened for the Diftaff. The Spider-Sags &ve of a Grey Colour when new 5 but turn blackifh when long expofed to the Ait: Indeed, one might find other Spider-bags of other Colours, and which would afford a better Silk, but their Scarcity would render

the Experiment difficult ; for which Reafon we confine our felves to the Bags of the commonett Spiders, which are the fhort-legg'd Kind. Thele always find out fome Place fecufe from the Wind and Rain, to make their Bags; as, hollow Trees, the Corners of Windows, or Vaults, or under the Eaves of Houfes. By collecting a Quantity of thefe Bags a new Silk is made, inferior in nothing to the common Silk. It takes all Kinds of Dyes, and may be made into all Kinds of Stuffs. M. Son had Stockings, and Gloves made of it, which he prefented to the Academy 5 and others to the Royal Society.

For the Manner of preparing the Bags to get the Silk, 'tis thus: After having gather'd 12 or 13 Ounces of thefe Bags, M. Sen had them well beaten for fbme Time with the Hand, and a Stick, to get out all the Duft : He then waftied them, in luke-warm Water, till they left the Water very clean: After this, he laid them to iteep, in a large Veffel, with Soap and Salt-petre, and Gum Arabic. The Whole was left to boil over a gentle Fire, for three Hours. The Bags were next wafli'd, in warm Water, to get out the Soap ; and, after all, laid to dry lame Days, to fit them for Carding ; which was p'erform'd by the common Silk- Carders, but with Cards much finer than ordinary. By this Means, he had a Silk, of a very particular Afh-colour, which was eafily lpun, and the Thread fpun from it, both Itronger and finer, than that of common Silk ; which fhews, that all lbrts of Work may be made of it : Nor is there any Reafon to fear, but it will itand any Trials of the Loom, after having pafs'd that of the Stocking-Weavers.

The only Difficulty, now, is in procuring a fufficient Quantity of Spider's Bags to make any contiderable Work of it : Which M. Son oblerves, would be no Difficulty at all, had we but the Art of Breeding them as they do Silk- Worms. For they multiply much more ; every Spider laying 6 or 700 Eggs, whereas the Silk-Worms don't lay above 100; yet are thele iait, ib tender, £$c. that one Half die with^ out making any Bags, or are hinder'd by fbme little Ac- cident, from making their Bags: Whereas the Spiders hatch of themlelve^, without any Care, in the Months of Augufi and September, in Fifteen or Sixteen Days after they are laid; the Old Spiders that lay them, dying foon after. The young Ones tnus bred, live Ten or Twelve Months without earing, and continue in their Bags without growing, till the hut Weatner putting their vifcid Juices in Motion, forces them to come forth, ipin, and run about to leek Food. Were a Way, therefore, found of breeding young Spiders in Rooms, they would, doubrleis, furnifh a much greater quantity of Bags than Silk-Worms do. For of Seven or Eight hundred young Spiders, which M. Son kept, icarce one died in a Year ; whereas of One hundred Silk-Worms, not Forty lived to make their Bags. M. Son having order'd all the ihort-legg'd Sliders that could be found in the Months of Augufi and September, to be brought to him, ihut them up in Paper Coffins, and Pots; covering the Pots with Papers^ which he pricked full of Pin-holes, as well as the Coffins, to give them Air. He fed them with Flies, and found fome- time afterwards the greateit part of them had made their Bags. The fame Excellent Perlbn found that Spiders Bags, with regard to their Weight, afford much mote M than thofe of the Silk-Worms. As a Proof hereof, he obferves, That Thirteen Ounces yield near Four Ounces of clear Silkt Two Ounces whereof, will make a Pair of Stockings; whereas Stockings of common Silk weigh Seven or Eight Ounces: Nor is there any Venom in the Silk, or even in the Spider, as many have imagined. M. Son has been bit by them leveral times, without any manner of harm ; and as for the Silk, 'tis uled with very good Succefs, to flop Bleeding and cure Wounds, the natural Gluten thereof acting as a kind of Batldm. It likewife yields, by Diltillation, leveral Specific Medicines, particularly great Quantities of Spirit, and Volatile Salt, which being prepared after the lame Manner as that drawn from the Bags of Silk-WvrmS, in making the Fnglifl] ^Drops, ib famous over all Europe ; may ferve to make other Drops of greater Efficacy, which M. Son calls Drops of Montpellier, to be uled in all fleepy Difeafes. M. Reaumur being appointed by the Royal Academy, to make a further Enquiry into this New Silk-worky has rais'd feveral Objections and Difficulties againft it ; which are found in the Memoirs of the Academy for the Year 1710- The Sum of what he has urged, amounts to this: The Natural Fiercenefs of the Spiders, renders them unfit to be bred and kept together, Four or Five thoufand being diftributed into Cells, 50 in (bme, 100 or 200 in others; the big Ones kill'd and eat thelefs, lb that in fhort time, there were fcarce left one or two in each Cell : And to this Inclina- tion of mutually eating one another, M. Reaumur afcribes the Scarcity of Spiders, confidering the vail Number of Eggs they lay. -But this is not all : He even affirms, That the Spider's Bag is inferior to that of the Silk-worm, both in Luftre and Strength ; and that it produces lefs Matter to be manufactured. The Thread of the Spider's Web only bears a Weight of Two Grains without breaking; that ot

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