Page:Cyclopaedia, Chambers - Volume 1.djvu/453

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CON

Conditional Conjunctions, in Grammar, arc thofe which ferve to make Proportions Conditional ; as, //, unkfi, pro- vided that, in caj'e of, &c.

Conditional Proportions, are fiich as confift of two Parts, connected together by the conditional Particle if. See Proposition.

Of thefe, the firO,' wherein the Condition lies, is call'd the Antecedent, and the other the Confequent. See Antece- dent, and Consequent.

Thus, if the Soul be Spiritual, it is immortal 5 is a condi- tional 'Proportion, wherein, if the Soul, &c. is the Antece- dent, and ts immortal the Confequent.

In Theology, we call the Knowledge of Conditionals, i. e. of conditional Truths, that Knowledge which God has of Things, confider'd, not according to their Effence, their Nature, or their real Existence 5 but under a certain Suppo- sition, which imports a Condition never to be accompliih'd.

Thus, when David aft'd of God whether the People of Ceila would deliver him up to his Enemies ; God, who knew what would befal in cafe David Should continue at Ceila, told him they wou'd deliver him : which he knew by the Knowledge of Conditionals.

Some of the Schoolmen deny that God has the Know- ledge of Conditionals : The Thomifls maintain, that God's Knowledge of Conditionals depends on a predeterminating Decree: Others deny it.

F. Daniel obferves, that the Truths which compofe the Knowledge of ■Conditionals, being very different from thofe which compofe the Knowledge of Intuition, and that of Understanding ; a third Clafs mult be added, and the Knowledge of God be divided into Intuitive, Intellective, and Conditional. Sec Knowledge.

CONDORMANTES, Religious Sectaries, whereof there have been two Kinds : The firil arofe in German'/, in the Xlllth Century ; their Leader a Native of Toleda. They held their Meetings near Cologne ; where they are faid to have worlhip'd an Image of Lucifer, and to have receiv'd Anfwers and Oracles from him : The Legend adds, that an Ecclefiallick having brought the Eucharift to it, the Idol broke into a thouland Pieces ; which put an end to the Worfhip.

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CON

The Com is generated by the Motion of a right Line\ KL round an immoveable Point K, called its Vertex, along the Circumference of a Plane, called its Safe, MN ■ or it may be conceiv'd as generated by the Revolution of the Tri- angle K L M, about the right Line K L, which is call'd tha Axis of the Cone; and KM its Lattts, or Side.

If the Axis be perpendicular to the Bafe, it is faid to be a right Cone ; and if inclined, or oblique, aftalcnous Cone.

Scalenous Cones arc again divided into ohtufe-anvled and acute-angled.

Euclid defines a Cone a folid Figure, whofe Bafe is a Cir^ de, as C D, (Fig. 3.) and is produced bv the entire Revo- lution of the Plane of a right-angled Triangle CAB, about the perpendicular Leg AB.

If this Leg, or Axis, be greater than C B, half the Bafe 3 the Solid produced is an acute-angled Cone : If iefs, an oh- tufc-anglcd Cone • and, if equal a right-angled Cone-.

But, Euclid's Definition only extends to a right Cone : that is, a Cone whofe Axis is at right Angles to the Bale ; and not to oblique ones, whofe Axis is not at right Angles to the Bale*

For a more general and comprehensive Defcription of a Cone, which may take in both right and oblique ones, Sup- pofe, an immoveable Point A, (Fig. 4.) without the Plane of the Circle EDEC; and Gippoie a right Line A E, drawn thro' that Point, and produced infinitely both ways, to be mov'd quite about the Circumference of the Cir- cle ; the two Superficies that will arife from this Motion, are each called Conic Superficies ; but, taken conjunctly, are called Superficies vertically oppojitc, or only oppqfite Super- ficies : The immoveable Point A, common to both the Su- perficies, is called the Vertex ; the Circle B D E C the 'Bafe j the right Line A C, drawn thro' the Vertex A and C, the Centre of the Safe ; and if infinitely produced, the Axis; and the Sohd comprehended under the conical Superficies and the Bafe, is a Cone.

'Properties of the Cone,

_ 1. The Area or Surface of every right Cone, excliifivc of its Safe, is equal to a Triangle whofe Safe is the 'Periphery, and us height the fide of the Cone. See Tri ingle.

her, Men J& ^^^g ^tffi^tJ^

and Women, young and old

The other Species of Condormantcs, were a Branch of Anabaptifis in the XVIth Century ; fo called, becaufe they lay, feveral of both Sexes, in the fame Chamber 5 on pre- tence of Evangelical Charity.

-fc/e-CONDUCT. See SAnz-Condutl.

CONDUCTOR, a Surgeon's Initrumcnt, which being put up into the Bladder, ferves to conduce the Knife, in the Operation of cutting for the Stone. See Lithotomy.

CONDUIT, a Canal, or Pipe, for the Conveyance of Water, or other fluid Matter. See Tube, %£c.

In the Earth are feveral fubtcrraneous Conduits, thro' which the Waters pafs that form the Sources of Springs ; and thro' which alfo pafs the Vapours, which form Metals and Minerals. Sec Spring, Metal, &c.

Artificial Conduits for Water, arc made of Lead, Stone, cad Iron, Pottery, &c. See Pipe, and Plumbery.

In the Province of New Mexico, there is faid to be a fub- tcrraneous Conduit, in form of a Grotto, extending o~oo Miles in length. See Duct.

CONDYLOMA, in Anatomy, the knitting of the Bones together in a Joncture or Articulation ; from the Greek kw- cftM©-, Jontture, Joining.

The Word is particularly ufed for the Jonctures of the Fingers, popularly called Knuckles. See Finger.

Condyloma, in Medicine, is a foft, painlefs Tumor, of the Oedematous kind, arifing on the internal Coat of the 'Anus, and the Mufcles of that Part, or in the Neck of the Matrix. See Oedema.

By long continuance it grows flefhy, and Ifiooting out as from a Stalk, takes the Denomination Ficus. See Ficus.

Condolymata are frequently the Effects of Venereal Ail- ments, and, if neglected, fometimes prove Cancerous : Their Cure depends on Mercurial Unffions, and proper Ef- charoticks to confume them ; tho Extirpation either by Li- gature or Irioifion, if the Nature of the Part will admit, is the mod expeditious. A Salivation is often neceffary, in or- der to facilitate and compleat the Cure.

The Word comes from kbpJVaw ; in regard the Condyloma has ufually Rug*, or Wrinkles, like the Joints of the Body.

CONDYLL'S, a Name AnatomiAs give to a little round Eminence or Protuberance at the Extremity of a Bone. See Bone.

Such is that of the lower Jaw, receiv'd within the Ca- vity of the Os ■Petrofum. See Maxilla.

When this Eminence is large, 'tis called the Head of the Bone. See Bone.

The Word comes from thc.Greek xwJV?.©-, Article, Joint.

CONE, in Geometry, a folid Body, having a Circle for its Bafis, and terminated a top in a Point, or Vertex. See Tib. Ceiiicks, Fig. 1. fee alfo Solid.

Hypothenufc of the right-angled Triangle deferring C B, the Bafe of the fame Triangle : that is, as the

C

height of the Cone Hence

to the Semidiameter of the Bafe.

irant

the Surface of a right Cone is equal to a Seaor of a Circle defcrib'd on the fide of the Cone, as a Radius, whole Arch is equal to the Periphery of the Cone ; and has therefore the lame Proportion to its Periphery which the Diameter of the Bafe has to the Sides of the Cone. See Circle.

Coroll Hence -we have a Method of deferring a Rets or Cage that f ball jufi cover a Cone.

Thus, with the Diameter of the Bafe AB, (Piate Co- mes, Fig. <$.) defcribe a Circle, and produce the Diameter to C, till A C be equal to the fide of the G-ne. To 2 AC andAB, determin'd in Numbers, and 3 60°, find a fourth proportional; and with the Radius C A, on the Centre C, de- fcribe an Arch DE equal to the Number of Degrees found ■ the Sector C D E with the Circles AB will be a Rete for the right Cone.

If, then, the fide of a truncated Cone be transferr'd from £j° ?' a £ nt i. an A / ch GH be defcrib'd with the Radius L.F ; by finding a fourth proportional to 340 , to ,'m num- ber of Degrees of the Arch GH, and to F C ; and vhence determining the Diameter of the Circle I F.'we Shall have a Net or Cover for the truncated Cone.

For C D B A E is a Net for rhe entire Cone ; C G F I H for the Cone cut off; therefore, DBEH for the -vuncated Cone,

2. Ernies and Pyramids, having the fame Safes and Alti- tudes, are equal to each other.

Now, '-tis Shewn, that every triangular Prifm may be di- vided into three equal Pyramids ; and therefore, that a triangular Pyramid is one third of a Prifm, Handing on the fame Bafe, and having the fame Altitude.

Hence, Since every multangular Body may be rcfolv'd into triangular ones, and every Pyramid is a third part of a Fri'm, having the fame Bafe and Altitude ; Since a Cone may be cSteem'dan infinite-angular Pyramid, and a Cylinder an infinite-angular Prifm ; a Cone is a third part of a Cylinder, which has the fame Bafe and Altitude.

Coroll. Hence we have a Method of mcafuring the Sur- face^ and Solidity of a Cone and a Cylinder.

Thus, for the Solidity : find the Solidity of a Prifm, or Cylinder, having the fame Bafe with a Cone, or Pyramid. See Prism, and Cylinder.

Which found, divide by 3 : the Quotient will be the So- lidity of a Cone, or a Pyramid.

Thus, v.g. if the Solidity of a Cylinder be ^055920^0, the Solidity of the Cone will be found 201864320,

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