Page:Cyclopaedia, Chambers - Volume 1.djvu/327

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CAT

Expulfion of the Moors. The Bollandijls pretend, the Tide was bore by their Predeceflbrs, the Vijigoth Kings of Spain ; and that Alexander VI. only renew 'd it to Ferdi- and and Ifabella. Others fay, that 'Philip dc Galois firft bore the Title ; which was given him after his Death by the Ecclefia flicks, on account of his favouring their Interests.

In fome Epiftles of the antient Popes, the Title Cathc- lick is given to the Kings of France, and of Jerufalem^ as well as to fereral Patriarchs and Primates. The Word is form'd from the Greek x*0' 'obx, v.niverfally ; whence rgfto- Mjeoj, univerfal.

Catholic Furnace^ is a little Furnace, fo contriv'd, as to be fit for all kinds of Operations, which do not require an intenfe Fire. See Furnace.

CATHOLICON of Spain. See Menippean Satyr.

Catholicon, in Pharmacy, a kind of foft Electuary ; fo call'd, as being fuppos'd univerfal ; or a Purger of all Humours. See Electuary.

Different Authors give different Recipes for it : That call'd Catholicon Nicholai is molt in ufe ; it confifts of 16 Ingredients, the chief whereof are Tamarinds, Caflia, Se- na, and Rhubarb. It is faid to be double, when there is a double Portion of Sena and Rhubarb.

The Catholicon for Clyjiers, only differs from this, in that it has no Rhubarb, and that Honey is us'd inftead of Sugar. See Clyster.

CATKINS, in Natural Hiftory, a Subftance growing on Nut-Trees, Birch-Trees, &c. in Winter time. See Plants.

CATLIN, among Surgeons, is a Difmembring Knife, for cutting orF any corrupted Part of a Body.

CATOPSIS, in Medicine, a Diforder of the Sight ; more ufually call'd Myopia. See Myopia.

CATOPTRICS, the Science of Refiex Vifion - 7 or that Branch of Optics, which delivers the Laws of Light, re- flected from Mirrors, or Specula. See Mirror, and Re- flection ; fee alfo Vision, Light, and Optics. Un- der which Heads, the Doctrine and Laws of Catoptrics are laid down.

The Word comes from the Greek tuefrw&t, Speculum 3 of KstT«, and opOstj/tt/, video, I fee.

Catoptrical T)ial, a Dial which exhibits Objects by reflected Rays. See Reflecting Dial.

Catoptric Telefcope, a Telefcope that exhibits Objefts by Reflection $ fee Reflecting Telefcope.

Catoptric Cijiula, a Machine, or Apparatus, whereby little Bodies are reprefented extremely large 5 and near ones extreamly wide, and diffus'd thro a vail Space 5 and other agreeable Phenomena, by means of Mirrors, difpos'd by the Laws o^Catoptrics, in the Concavity of a kind of Cheft.

Of thefe there are various Kinds, accommodated to the various Intentions of the Artificer : Some multiply the Objects 5 fome deform 'em ; fome magnify, &c. The Structure of one or two of 'em, will iurflce to Jhew how in- finite more may be made.

To make a Catoptric CiJliUa, to reprefent Jeveral dif- tintl Scenes of Ob je Lis, when loolCd in at fever al Foramina, or Holes. t ,

Provide a polygonous Cijlula, or Cheft, of the Figure of the Multilateral Frifm A B CD EF, (Plate Optics, Fig. 19.) and divide its Cavity by Diagonal Planes E B, F C, DA, interfecting each other in the Centre G, into as many trian- gular Locules, or Cells, as the Cheft has Sides. Line the Diagonal Planes with plane Mirrors : In the lateral Planes make round Holes, thro which the Eye may peep within the Locules of the Cheft. The Holes are to be cover'd with plain Glafles, ground within-fide, but notpolifti'd, to prevent the Objects in the Locules from appearing too dilHnctly. In each Locule are plac'd the different Objects, whofe Ima- ges are to be exhibited ; then covering up the Top of the Cheft with a thin tranfparent Membrane, or Parchment, to admit the Light, the Machine is compleat.

For, from the Laws of Reflection, it follows, that the Images of Objects, plac'd within the Angles of Mirrors, are multiply'd, and appear fome more remote than others ; whence the Objects in one Locule, will appear to take up more rooin than is contain'd in the whole Cheft. By looking, therefore, thro one Hole only, the Objects in one Locule will be fcen ; but thofe multiply'd, and diffus'd thro a Space much larger than the whole Cheft : thus every new Hole will afford a new Scene : According to the different Angles the Mirrors make with each other, the Re pre fen rat ions will be different 5 if they be at an Angle greater than a right one, the Images will be monftrous, &c. See Anamorphosis.

The Parchment that covers the Machine, may be made pellucid, by wafhing it feveral times in a very clear Lye, then in fair Water, and bracing it tight, and expo- fing it to the Air to dry. If 'tis defir'd to throw any Co- lour on the Objects, it may be done by colouring the Parch- ment. %abnius recommends Verdigreafe, ground in Vine- gar, for green ; Decoction of 'Brafil Wood, for red, $£c. He adds, it ought to be varnifh'd, to make it Iriine;

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9o make a Catoptric Cijlula, to reprefent the Objects within it prodigioufly multiply'd, and diffus'd thro a vafi Space.

Make a polygonous Cijlula, or Cheft, as before, but with- out dividing the inner Cavity .into any Apartments or Lo- cules ; (Plate Optics, Fig.20.) line the lateral Planes C B H I, B HL A, A L M F, &c. with plane Mirrors, and at the Fo- ramina, or Apertures, pare off the Tin andQuickfilver,that the Eye may fee thro : Place any Objects in the Bottom MI, v.g. a Bird in a Cage, &c.

Here, the Eye looking thro the Aperture h 2, will fee each Object plac'd at bottom, vaftly multiply'd, and the Images remov'd at equal Diftances from one another. Hence, were a large multangular Room, in a Prince's Pa- lace, lin'd with large Mirrors, over which were plain pel- lucid Glaffes to admit the Light $ 'tis evident the Effects would be very furprifing and magnificent. See Mirror, Reflection, £5?c.

CATOPTROMANCT, a kind of Divination, among the Antients ; fo called, becaufe confuting in the Applica- tion of a Mirror 3 from v.o.to4\t^v, Speculum, and ^a-CTtjei, T)ivinatio. See Divination.

Paufanias fays, it was in ufe among the Achaians, where thofe who were lick, and in danger of Death, let dowrt a Mirror, faften'd by a Thread, into a Fountain before the Temple of Ceres, then, looking in the Glafs, if they few. a gaftly disfigur'd Face, they took it as a lure Sign of Death : on the contrary, if the Face appear'd frcfti and healthy, 'twas a Sign of Recovery.

CAVA, in Anatomy, the Name of a Vein, the largeft in the Body, terminating in the right Ventricle of the Heart 5 where it opens with a large Yvlouth, to convey to it the Blood brought from all the Parts of the Body, by the Branches of the other Veins, which all terminate in the Cava. See Vein.

At its Entrance into the right Ventricle, it has three membranous Valves, call'd Tricufpides, or jfriglochines, from their triangular Figure ; fo accommodated, as to al- low the Blood's paffage from the Cava to the Heart, and to prevent its return. See Heart, and Valves.

The Cava is divided into the afcend'wg and defending Parts : The afcending Cava, is that which arifes from the lower Parts 5 fo call'd, becaufe the Blood hereby convey'd to the Heart, mounts, or afcends. The defending Cava comes from the upper Parts, and is fo called, becauie the Blood hereby brought from the Brain, and other Parts, defcends. See Blood, and Circulation.

CAVALCADE, a formal, pompous March, or Procef- fion of Horfemen, Carriages, £*?c. by wayof Parade, or Cere- mony. See Carrousal, Tilt, Quadril, $£-c.

CAVALEER, or CAVALIER, a Horleman, or Perfon mounted on Horfeback. Antiently, the Word was reftrain'd to a Knight, or Miles. See Knight, and Miles. The French ftill ufe Chevalier in the fame Senfe. See Che- valier.

Cavalier, in Fortification, a Terrace, or Platform, commanding all around the Place. 'Tis rais'd ib>, or 29 Foot high, atop of a Rampart, tor placing the Cannon on, and fecuring the Country about. 'Tis fometimes alfo made in the Country, to play in upon the Town ; and as much above the other Works, as a Man on Horfeback is above a Footman 5 whence the Denomination.

In form, the Cavalier is fometimes round, and fometimes fquare 5 having always a Parapet to cover the Cannon : Its Breadth depends on the Number of Pieces to be lodg'd on it ; there being always allow'd an Interval of 10 or 12 Foot between each two, for the Conveniency of loading and firing.

The Cavalier is alfo fometimes call'd a double Sajlion.

Cavaliers, or Cavaleers, confider'd as a Faction ; fee Tory.

CAVALRY, a Body of Soldiers, who fight, or march on Horfeback. See Soldiers 5 fee alfo Guards.

The Englifh Cavalry is divided into Horfe, and dra- goons -, the French into Companies of Ordnance, as the Gardes du Corps, Gens dArmes, Light-Horfe, &c. and in- to Regiments, commanded by Mejhres de Camp. The Dragoons, among the Englijh, and the Regiments among the French, form what they call the light Cavalry. When an Army is rang'd in order of Battel, the Cavalry is polled on the Wing'.

Bodies of Cavalry, rang'd in form of Battel, are call'd Squadrons. See Squadron.

The Romans, in their firft Wars, were unacquainted with the ufe of Cavalry, and made their whole Force confift in Infantry ; infomuch, that even in the Engagement they made their Horfe difmount, and fight on Foot ; never re- fuming their Horfes, but to purfue the Enemy the better when routed. It was the Cavalry otPyrrbus, that firft occafion'd them to alter their Sentiments 5 but efpecially that of Hannibal, which ftruck them with fuch a Terror, that the invincible Reman Legions durft not attack them on even Ground.

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