Page:Cyclopaedia, Chambers - Volume 2.djvu/452

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P O I

(H3

P 01

yet intimating Ibmething to come after it ^ — this we call a nite : Tho' in Practice we only diftinguifh 3 2 of them. See

Colon. See Colon. Compass.

A Point with a Virgula, call'd a Semicolon, marks a Senfe Some ufe Point, for the Interfeflion of a Vertical Circle,

lefs compleat than the Colon ; tho' Authors (rem to ufe with a Circle parallel to the Horizon; and even fome, for

them indifferently •, nor are Grammarians agreed about their the Segment of a Vertical intercepted between the Meridian

precife Difference. See Semicolon. and Horizon, or a Circle parallel thereto.

The Virgula, call'd Comma, marks a Sub-divifion of a The Points are (hewn by right Lines drawn from a Point

Member of a Period. See Comma. affumed in a horizontal Plane.

A Point of Interrogation, as ? marks fomething to be pro-

as intimating a Queftion ask'd. fudden Surprize and

nounced in a higher Tone : See Interrogation.

A Point of Admiration ! marks a Wonderment. See Admiration.

Our Points and Accents were entirely unknown to the Ancients. And in the ancient Greek Manufcripts, the whole feems wrote with the fame ftroke of the Pen ; the .Words and Letters being join'd throughout.

In after-times, Point s were invented and added a-top of the Letters, to fhew when the Senfe was finifh'd ; hence the Gram- marians coming to retouch the old Manufcripts thought fit

to add the Points and Accents. -Salmafius affirms, that he

has even obferved, plainly, where they have been added, by the difference of Hands. See Accent.

Points, in the Hebrew Learning, are certain Cha- racters, which, in the Writings of that Language, ferve to mark the Vowels ; which, in effect, are only Points. See Vowel.

The Antiquity of the Points in the Hebrew Tongue makes the Subject of a celebrated Controverfy among the Learned; Ibme maintaining their Origin to be the fame with that of the Hebrew Language -, and others afferting them to have been firft introduced by Efdras, after the Babylonifti Captivi- ty, when he compiled the Canon, tranfcribed the Books in- to the prefent Chaldes Character, and reftored the Purity of the Hebrew Text.

Others will have them invented by the Doctors of the School of Tiberias, ufually called the Mafforetes, five or fix hundred Years after Chrift.— The Rabbin Ettas Levita was the firfl: who ftarted this queftion in the laft Century ; and maintain'd them to have been an Invention of the Maffo- retes, for the Eafe of thofe who were to leam the Hebrew Tongue. See Massoretes.

This Sentiment was efpous'd by Capella, to whom adher'd Luther, Calvin, Cafaubon, Scaliger, 8cc.—Buxtorf attack'd Ca-

So that a Point of the Compafs, is popularly taken for a 32d Part of the whole ; or for an Arch of 1 1 Degrees i%- Minutes-, half of which, •»&.. 5° 38' is cill'da half a Pohtt-j and half of that, or 2 49' a Quarter Point. See Compassj

Thefe Points of the Compafs are divided into Cardinal and Collateral.

Cardinal Points are the Interfeftions of the Horizon and Meridian, call'd the North and South Points; and the Inter- fections of the Horizon with the Prime Vertical, call'd the Eafi and Well. See North, South, &c.

Thefe coincide with what the Latins call Cardincs Muri- di ; and are a Quadrant, or go Degrees, diftant from each other. See Cardinal.

Collateral or Intermediate Points, are thofe lying between the Cardinal Points. — Which are either Primary, viz.. thofe equi-diftant from the two Cardinals, as North-Eaft, South- Wefl, &c.

Or Secundary, which are again, either of thejky? Orderi, viz.. fuch as are equidiftant from a Cardinal and the next Primary, as North-North-Eaft ; or of the fecond Order, i. e. equidiftant between a Cardinal or Primary, and firft Secundary, as North-Eaft by North.

The Primary Collateral Points, therefore, are 45 diftant from the Cardinals-, the firft Secundaries 22 30' from the Cardinal and next Primary Collateral-, and the Secundaries of the fecond Order ii° 15' from a Cardinal, or firft Colla- teral, and a Second. See Collateral.

Point, among Seamen, is alfo ufed for a Cape, or Head-Land, jetting out into the Sea. See Cape.

They fay, two Points of Land are one in another, when they are fo in a right Line againft each other, as that the innermoft is hindered from being feen by the outermoft.

Point, in Perfpective, is a Term ufed for various Parts or Places, with regard to the Perfpective Plane. See Perspective Plane — Such are, the

Point of Sight, or View, or of the Eye, is a Point on the

fella violently on this Article, and gain'd a great Number of Plane, as F, (Tab. Pcrfpeltive Fig. 12.) mark'd out by a

Divines on his Side, who took the Alarm -, imagining it a grievous Wound to the holy Text, to allow the Vowel- Points to have been added by the Mafforetes, and not to have been found inthe ancient Text ; becaufe without thefe 'tis ve- ry difficult to fix the reading thereof. — Yet in the Samaritan Text there is no Point or Vowel, nor in many of the mod ancient Hebrew Manufcripts. See Hebrew, $V.

Point, in Mulick, a Mark or Note anciently ufed to diftinguifh the Tones. See Note.

Hence we ftill call it Simple Counter- Point, when a Note of the Bafs, anfwers precisely to that of the Treble ; and Fi- gurative Counter-Point, when a Note is fyncopeed, and one of the Parts makes feveral Inflexions of the Voice or Tone, while the other only makes one. See Counter-point,

We ftill ufe a Point to raife the Value of a Note, and prolong its Time by one half, e.gr, a Point added to a Semi- breve, inftead of two Minims, makes it equal to three. See Time, and Characters in Mvfick.

Point, in Aftronomy, is a Term applied to certain Parts or Places mark'd in the Heavens ; and diftinguifhed by proper Epithets.

The four Grand Points or Divifions of the Horizon, viz.. the Eafl, Weft, North, and South, are call'd Cardinal Points. See Cardinal; fee alfo East, West, &c. each under its proper Article.

The Zenith and Nadir are the Vertical Points. See Ver- tical, Zenith and Nadir.

The Points wherein the Orbits of the Planets cut the Plane of the Ecliptic, are call'd the Nodes. See Node.

The Points wherein the Equator and Ecliptic interfect,

are call'd the Equinoctial Points. See Equinoctial

Particularly, that whence the Sun afcends towards the North-Pole, the Vernal Point ; fee Vernal : And that by which he defcends to the South-Pole, the Autumnal Point. See Autumnal.

The Points of the Ecliptic, where the Sun's Afcent above the Eqnator, and Defcent below it, terminate, are call'd the Solfiitial Points; fee So lst i ti al.— Parti- cularly, the former of them the Eflival or Summer Point, fee S u m m e R ; the Latter the Brumal or Winter Point, fee Winte R,Ch\

Point, in Navigation and Geography. — Points of the Horizon, or of the Compafs, are certain Points form'd by the Interfections of the Horizon, with Vertical Circles. See Horizon.

The Number of thefe Points, therefore, is really the fame With that of the Points conceiv'd in the Horizon, i. e. infi-

rightLineBF, drawn from the Eye, perpendicular to the Plane, call'd alfo the Principal Point. See Vision; fee alfo Principal.

This Point is in the Interlection of the Horizontal and Vertical Planes. See Plane.

Some Authors call the Point wherein the Eye is actually placed, and where all the Rays terminate, as O, the Point of Sight or Vifion ; and define the Principal Point to be that wherein all the Lines drawn from the horizontal Plane to the Line of View or Diftance, terminate. See Principal. P 1 n T of Diftance is a Point , v. gr. P or Q, in the ho- rizontal Line PQ, at the fame Diftance from the principal Point V, as the Eye O, is from the fame. See Distance.

Third Point is a Point taken at Difcretion in the Line of Diftance, wherein all the Diagonals drawn from the Divi- fions of the Geometrical Plane, concur.

Objective Point, a Point on a Geometrical Plane, whofe Reprefentation is required on the Perfpective Plane.

Point, in Opticks— The Point of Concourfc, or Con- currence, is that wherein converging Rays meet ; more ufu- ally call'd the Focus. See Focus.

Pointu/ Difperfion, is that wherein the Rays begin to di- diverge; ufually call'd the Virtual Focus. See Virtual. Point of Incidence, is a Point on the Surface of a Glafs, or other Body, wherein a Ray falls. See Incidence.

Point of View, with regard to Building, Painting, &c. is a Point at a certain Diftance from a Building, of other Object, wherein the Eye has the moft advantageous View, or Profpect of the fame.

This Point is ufually at a Diftance equal to the Height of the Building — For an inftance,— To confider with Judgment, the whole of the famous Church of the Invalides at Paris ; we 111 uft not ftand at above 340 Foot diftance from it, which is nearly its Height. To be able to judge of the Or- donnance of its Facade or Frontifpiece, and the Regularity of its Order, the Eye fhould be as far off as the Fiontifpiece is high, viz.. 100 Foot. l

But to examine the Correftnefs of its Profiles, and the Spirit of its Ornaments; the Eye fhould only be diftant the Height of the Doric Order, which is about 40 Foot ; if it be nearer, the Parts too much fhortened will appear out of Proportion.

A Vague or indeterminate Point has a different EfFeft from the Point of View; in that, in looking at a Building from an indeterminate Point ; the Eye can only form an Idea of the Magnitude of its Mafs, by comparing it with other Buildings adjacent to it.

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