Page:Cyclopaedia, Chambers - Volume 1.djvu/380

 C I R

C 22d )

C I R

that a little before the Time when he wrote, Grcmtcijim had pafs'd from the Colckide, to the People inhabiting near Thermodcon and Parthenius.

Mar/bam is of Opinion, that the Hebrews borrow'd Gr- cumcijion from the Egyptians ; and that God was not the firlt Author thereof: citing Diodorus Siculus and Herodotus as Evidences on his fide. Be this as it will, 'tis certain, the Practice of Circumcifion among the Hebrews, diffcr'd very confidcrably from that of the Egyptians.

Among the firft, 'twas a Ceremony of Religion, and was perform';! on the eighth Day after the Birth of the Child. Among the latter, a Point of mere Decency and Cleanlinefs; and, as fome will have it, of phyfical Neceflity : and was not pcrform'd till the thirteenth Year ; and then on Girls as well as Boys.

Among the Jen's, Circumcifion was perform'd with a Knife of Stone. They fet afide the Practice of Circumci- fion, during the forty Years of their Paffage thro' the Wil- ernefs; in regard, Circumcifion being intended as a Mark of Diftinclion between the Jews and Gentiles, it was unne- ceffary to make any Mark at all, in a Place wherein there was no body ro mix with them.

M. Floury obferves, that the Jews were not unanimous as do the Neccffity of Circumcifion ; fome holding it an Effen- tial, others as a Circumftance.

The Turks, before the Operation of Circumcifion, fqueeze the Skin with little Pinchers, to deaden the Senfation : they then cut it off with a Razor, and apply a certain Pouder, which heals the Wound, and abates the Pain. They never circumcife till the fevenrh or eighth Year; as havingno No- tion of its being neceffary to Salvation.

The Perfians circumcife their Boys at thirteen Years ; and their Girls from nine to fifteen. Thofe of Madagascar cut off the Flefh at three feveral times : The molt zealous of the Relations prcfenr, catches hold of the Preputium and fwallows it.

Herrera tells us, there is a kind of Circumcifion among the Mexicans, tho they are very remote both from Judaifm and Mahomctanijm : they cur off the Forefkin of the virile Member and the Ears, as foon as the Child is born, with a world of Ceremony.

Circumcifion is alfo pracfis'd on Women, by cutting off the Fore-fkin of the Clitoris ; which bears a near refemblance, and analogy to the Prtfputium of the Male Penis. Strabo fays, the EgyptianWomcn were circumcis'd ; Selon fays the fame of the Copht<£ ; and f. Jovius and Munfier of the Subjects of Prefter John. See Clitoris.

Among the Jews, the Fathet is oblig'd to have his Son circumcis'd on the eighth Day ; it mayn't be fooner : but the Child's Weaknefs may allow of its being deferr'd longer. There is a Godfather to hold the Child, and a Godmother to carry it from the Houfe to the Synagogue, and to prefent it there. He who circumcifes is call'd in Hebrew, Mohel : Any Pcrfon is chofen for the Purpofe, indifferently ; provided he be but capable of the Function ; which among the Jews is a Title of great Merit.

The Manner of rhe Ceremony, as related by Leo de Mo- dena, is as follows.

Two Seats are prepar'd, in the Morning, with filken Cu- shions ; the one for the Godfather who holds rhe Child, the other, as they fay, for the Prophet Elias, whom they fup- pofe to aflift invifibly. The Pcrfon who is to circumcife brings the neceffary Utenfils, the Razor, Styptic, Linen, Fillet, and Oil of Rofes ; to which fome add a Shell full of Sand to put the Tneputium in. A Pfalm is fung till the God- mother brings the Child, attended with a Croud of Wo- men, and delivers it to the Godfather ; none of 'em entering the Door. The Godfather being feated, fets the Child on his Lap : then the Cicumcijer taking the Razor, and pre- paring the Child for the Operation, fays, Blej/ed be thou, O Lord, who hafi enjoin' d us Circumcifion ; and in fo faying cuts off the thick Skin of the freputium, and with his Fin- ger Nails tears off another finer Skin remaining ; fucking the Blood two or three times as it breaks our, and (pitting it out into a Glafs full of Wine : then he lays Dragons-Blood on the Wound, with Pouder of Coral, and other Things to flanch the Blood ; and laftly, a Comprefs of Oil of Rofes; and thus binds up the whole. This done, he takes a Glafs of Wine, and bleffing it, adds another Benediction for the Child, and impofes the Name.

The Manner of Circumcifing among the Turks, differs from that of the Jews : for rhe former, after rhey have cut off the Skin, meddle no further ; but the laft tear off the Edge of the remaining Skin in feveral Places with their Thumb- Nails ; which is the Reafon why the circumcis'd Jews are cur'd much fooner than the T'urks.

Thofe among the Jews who perform the Operation of Cir- cumcifion, are diftinguiftl'd by the Length of their Thumb- Nail-'.

Circumcision is alfo the Name of a Feaft celebrated on the firil of January, in Commemoration of the Circumcifion of our Saviour. See Feast.

This Day was antiently kept a Faft; in oppofition to th Pagan Superttitions, who feaited on it in honour of the C 1 Janus.

CIRCUMFERENCE, in Geometry, the Curve Lin that inclofes a Circle, or circular Space ; call'd alfo Peritih ^ ry. See Circle, and Periphery.

All Lines drawn from the Centre of a Circle to the Cir- cumference, call'd Radii, are equal. See Radius.

Any Part of the Circumference is called an A, ch ; and a right Line drawn from one Extreme of the Arch to th* other, a Chord. See Arch, and Chord.

The Circumference of every Circle is fuppos'd to be di- vided into 3<So equal Parts, ca\V A Degrees. See Decree

The Angle at the Circumference, is double that at the Centre. See Angle, and Centre.

Every Circle is equal to a Triangle, whofe Bafe is equal to the Circumference, and its Height to the Radius. See Triangle.

Hence, the Circumferences of Circles are to each other as their Radii.

Hence, again, fince the Circumference of one Circle is to its Radius, as that of any other Circle to its Radius ; the Ratio of the Circumference to the Radius is the fame in all Circles.

The Ratio of the Diameter of a Circle to its Circumfe- rence, Archimedes makes as 7 tou ; others, who bring it nearer the Ttuth, as ioooooouooooooooo to 3 141 592653 58- 97932. For Ufe, the Proportion of 100 to 314 in fmaller Circles; and of 1000 to 3145 in larger Circles, is com- mended by Victa, Huygens, Sec. The jufteft Proportion for fmall Numbers, is that of Metius, who makes it as 113 to 355. See Diameter.

The Diameter of a Circie therefore being given, its Cir- cumference is had ; and that multipiy'd by one fourth Part of the Diameter gives the Area of the Circle. See Area.

The Word is forin'd from the Latin Circum, about, and fero, I carry.

CIRCUMFERENTOR, an Inftrument us'd in Survey- ing, to take Angles by. See Angle, and Surveying.

Tho Circumferentor is very fimple, yet expeditious in the Practice : Ir confifts of a Brafs Circle and an Index, all of a piece. See its Figure in Tab. Surveying, Fig. 19.

On the Circle is a Card, or Compafs, divided into ;6o Degrees; the Meridian Line whereoi anfwers to the middle of the Breadth of the Index. On the Limb, or Circum- ference of the Circle, is folder'd a Brafs Ring ; which, with anorher fitted with a Glafs, make a kind of Box for the Needle, which is fufpended on a River in the Centre of the Circle. To each Extreme of rhe Index is fitted a Sight. See Sights.

The whole is mounted on a Staff; with a Ball and Socket for rhe Conveniency of its Motion. See Ball and Socket. Ufe of the Circumferentor.

To take an Angle by the Circumferentor. Suppofe the Angle rcquir'd E K G, (Tab. Surveying, Fig. 20.) place the Inftrument, v. g. at K, with the Flower-de-luce in the Card towards you. Then direct the Sights, till thro' em you fpy E ; and obferve what Degree is pointed at by the South End of the Needle, which fuppofe 296 : then turn the In- ftrument about, the Flower-de-luce frill towards you, and di- reft the Sights to G ; noting the Degree at which the South End of rhe Needle points, which fnppoie 1S2.

This done, fuhtracfing the lefTer Number 182, from the greater 290", the Remainder 114, is the Number of Degrees of the Angle E K G.

If the Remainder chance to be more than 180 Degrees, it muff be again fubtracfed from 360 Degrees ; rhe laft Re- mainder is the Quantity of the Angle fought.

To take the Plot of a Field, Wood, 'Park, &c. by the Circumferentor.

Suppofe ABCDEFGK, (Fig. 21.) an Indofure to be furvey'd with the Circumferentor.

1. Placing the Inftrument at A, the Flower-de-luce to- wards you, direct the Sights to B ; where, fuppofe the South End of the Needle to cut 191 ; and the Ditch, Wall, or Hedge, meafur'd with the Chain, to contain 10 Chains, 7! Links ; which enter down. See Chain.

2. Placing the Inftrument at B, direct the Sights as before to C; the South End of the Needle, v.g. will cut 279 ; and the Line BC conrain 6 Chains 83 Links, to be noted as be- fore. Then move the Infttument to C ; turn the Sights to D, and meafure C D as before.

In rhe fame manner, proceed to D, E, F, G, H, and laft- ly to K; ftill noting down the Degtees of every Bearing, or Angle, and the Diftances of every Side.

Having thus gone round the i : ieid, you will have a Table in the following form.

Stations. Degrees. Min. Chains. Links.

A 191. 00 10. 75

B 297. 00 6. 83

C 2i<s. 30 1. 82

&c.

From