Page:Cyclopaedia, Chambers - Volume 2.djvu/427

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PLA

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P LA

Thus the right Line R S {fame Fig.)^ defigns the Heliocentric Place, or Place re.duc'd to the Ecliptic.

Geocentric Vl ace is that Point of the Ecliptic, to which a Planet view'd from the Earth is referr'd. See Geocen- tric.

Thus, N E O R (fame Fig.) reprefenting the Ecliptic, &c. TR will reprefentthe the Geocentric Place.

Place of Radiation, in Optics, is the Interval, or Space in a Medium or tranfparent Body, thro' which any vifible Objeft radiates. See Radiation, &c.

Place, in Geometry, is a Line ufed in the Solution of Problems ; more ufually call'd by the Latin Name Locus.

See the Doctrine of Geometrical Places, under the Article Locus.

Place, in War, is a genera! Name for all kinds ef For- trefles, where a Party may defend themfelves ; and may be defined to be a Place fo difpofed, as that the Parts which encompafs, it defend and flank one another. See Fort and Fortification.

A Strong Place, is a Place flank'd and cover'd with Bafli- ons. See Bastion.

Regular Place, is that whofe Angles, Sides, Baftions, and other Parts are equal ; and is ufually denominated from the Number of its Angles, as a Pentagon, a Hexagon, &c. See Pentagon, Hexagon, <$-c.

Palma nova, built by the Venetians, is a Dodecagon. See Dodecagon.

Irregular Place is that whofe Sides and Angles are un- equal.

P L A c e of Arms, in Fortification, is a ftrong City, or Town, pitch'd upon for the chief Magazine of an Army. See Arms.

Place of Arms in a City, is a large open Spot of Ground, where the Garrifon holds its Rendezvous at Reviews, and in Cafes of Alarm, to receive Orders from the Governor. See Garrison.

Place of Arms in a Siege is a fpatious Place cover'd from the Enemy, where the Soldiers are kept ready to fu- ftain thofe at work in the Trenches, and to be commanded to the Places where they are wanted.

Places/ Arms particular, in a Garrifon, is a Place near every Baftion, where the Soldiers, fent from the grand Place to the Quarters affigned them, relieve thofe that are either upon the Guard, or in fight.

Place of Arms without, is a Place allowed to the Co- vert Way, for the planting of Cannon, to oblige thofe who advance in their Approaches to retire.

PiACEif Arms in a Camp, is a large Space at the Head of the Camp, for the Army to be rang'd in and drawn up in Battalia.

There is alfo a Place (or each particular Body toaflemble in. See Camp.

P l a c e of Arms of a Troop, or Company, is the Spot of Ground on which the Troop, or Company, is drawn up_ See Troop, Ore.

Place, among Logicians, Orators, &c. is the Seat of an Argument, or that from which it is taken. See Argu- ment and Topic.

There are two forts of Places, viz. Inartificial and Arti- ficial.— -The firff, the Place ol Teftimony, Authority, &c. The fecond, that of Reafon ; as when we argue from Uni- verfals, e. gr. from Genus, Species ; from Caufes, as the End, Efficient, Matter, Form, &c.

Common Place. See Common Place. Place of "Units, Tens, &c. See Unit and Numera- tion.

PLACENTA, in Anatomy, a foftilh Mafs, found in the Womb of a pregnant Woman; wherein the Ancients fuppofed, the Blood was purified and prepared for the Nou- rilhment of the Foetus. See Foetus.

Hence they alfo call'd it Hepar "Uterinum, the Liver of the Womb ; as if it did the Office of a Liver in preparing the Blood. See Liver.

It is call'd by the Moderns Placenta, q. d. Cake or Cheefc- Cake ; becaufe in Form of a Cake.

The Placenta is fuppofed by fome to be only a Mafs of co- agulated Blood ; for in the prefijng, or waffling it, it dif- folves ; and its real Ufe to be, to ferve as a Pillow for the Umbilical Veflels to reft on. See Umbilical.

Its Figure is not unlike that of a Plate without Brims-, three quarters of a Foot over, and fometimes a Foot. It is round, generally Concave or Convex. The Concave Side adheres to the Uterus, and is uneven, having divers Protube- rances and Pits, by which it makes Impreflions upon, and

receives them from, the Uterus Its Place in the Uterus,

whatever fome pretend, is not certain.

In Women, unlefs in cafe of Twins, &c. there is but one: However, the Number generally anfwers the Num- ber of the Foetus In fome Brutes, efpecially Oxen or

Sheep, they are vere numerous, fometimes near an hundred, even for one Foetus, fmali, and refembling pretty large conglo- merate Glands.

From the external or concave Side; which likewife has its Protuberances, tho' cover'd with a fmooth Membrane, iffu e the Umbilical Veflels, which are in great Plenty diftributed thro' the whole Subftance of it. See Umbilical.

Some even imagine this Part to be nothing elfe but 3. Plexus of the Vein and Arteries, by whofe Extremities - pening into the Sides of the Hypogaftrick Veflels, the Cir- culation is perform'd between the "Mother and the Fcetus- for that fide of the Placenta, which adheres to the Womb' appears to be- nothing but the Extremities of an infinite Number of fmall Threads, which, in Labour, dropping out of the Pores in the fides of the Hypogaftrick Blood- Veflels, into which they had infinuated themfelves, is the occafion of the flowing of the Lochia, 'till the Uterus colhpfes, or. the Pores, by the natural Elafticity of the Veflels, contrail by Degrees. See Lochia.

'Tis a great Difpute among the Anatomifts of the Royal Academy of Paris, whether the Placenta have any external Coat, whereby it is connected to the Womb.— M. Aiery maintains it has none; and that nothing hinders the Blood of the Mother from palling out of the Womb into the Pla- centa and thence to the Fcetus : In which Opinion he is fe- conded by M. Rohault. MefT. Vicuffens and Winfloxv main- tain the contrary ; in a fubrequent Memoir M. Rohault en- deavours to fhew, that the Placenta is no particular Part, but only a Portion of the Chorion condens'd or thicken'd. See Chorion.

P L A C 1 T A, Pleas, a Term frequent in our Laws and Cuftoms. See Plea.

Originally, Placita fignified certain publick Aflemblies, of all Degrees of Men, wherein the King prefided, and where the great Affairs of the Kingdom Were confuted upon.

Thefe Aflemblies were call'd Placitrf generalia ; becaufe General it as univerj'orum major urn tarn Clericorum quam Laico- rum ibidem conveniebat — And, hence, the Decrees, Ordi- nances, Sentences, &c. of the Aflembly were alfo call'd Placita.

Sim. Dunelmenjis tells us they were held in the open Fields; for, fays he, Nullamoportet Regem in Uteris ajjignare curiam, quia ubi rex judicat in aperto, tbi eft Curia fua. See Court and Curia.

Some will have thefe Placita generalia, and Curia Regis, to be much the fame with what we now call a Parliament. See Parliament.

The Lords Courts came hence alfo to be call'd Placita ge- neralia, tho' oftener Curia generates; becaufe all their Te- nants and Vaffals were obliged to appear in them. See Lord Vassal, &c.

We alfo meet with Placitum nominatum, for the Day ap- pointed a Criminal to appear in and make his Defence, Leg.

Hen. I. And Placitum fraclum, i. e. when the Day is

laps'd.

My Lord Coke derives the Word a placendo, quia bene pla- citare fuper omnia placet. Indeed this feems a very fanciful Definition; and others have more Reafon in deriving it from the German Plats, or the Latin Plateis, Fields, 01 Streets, where thefe Aflemblies were originally held.

PL AC I TARE, in the old Law-Books, fignifies to plead Caufes. See Pleading.

Atfos p\&citzndi awe conq'feftum, fuit coram aldermanno, Cr proceribus, Cfr eorum Hundredariis, fc. Baronibus, Majoribus, Melioribus, Senioribus & Vrbanis. Mf. in Bibl. Cott. fub Tit. Vitellius.

Hence, Placitator, a Pleader.— Ralph Flambard is recorded to be totius Regni Placitator, in William the fecond's Time.

PLACITUM, in Law, a Sentence of the Court ; or an Opinion, Ordinance, or Decree. See Sentence, Decree, Canon, crc.

PLAFOND, orPLATFOuND, in Architecture, the Ceiling of a Room, whether it be flat or arched ; lin'd with Plalter, or Joiners-Work, and frequently enriched with Paintings, Chr. See Cieling.

P L a f o n d is alfo more particularly ufed for the Bottom of the Projefture of the Larmier of the Corniche ; call'd al- fo Sofit. See Sofit and Larmier.

PLAGIARY, in Philology, Author-Theft ; or the Pra- ftice of purloining other Peoples Works, and putting them off for a Man's own.

Among the Romans, Plagiarius was properly a Perfon who bought, fold, or retain'd, a free Man for a Slave; fo call'd, becaufe the Flavian Law condemned fuch a Perfon to be whipp'd, adplagas. See Slave.

Thomafm has an exprefs Treatife de plagio litterario ; wherein he lays down the Laws and Meafures of the Right which Authors have to one anothers Commodities.— Dictio- nary- Writers, at leaft fuch as meddle with Arts and Scien- ces, feem exempted from the common Laws of Meum and Tuum ; they don't pretend to fet up on their own bottom, nor to treat you at their own Colt.

Their Works are fuppofed, in great Meafure, AfTemblages of other Peoples ; and what they take from others they do it avowedly, and in the open Sun,— In effeCt, their Quality

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