Page:Cyclopaedia, Chambers - Volume 2.djvu/426

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PITUITARY Gland is a Gland in the Brain, (bmewhat difficult to be feen without removing it Out of its Place. See Brain.

It is of the Size of a very large Pea, in the Sella of the Os Sphendides, under the Infundibulum, wherewith it com- municates ; receiving from it a Lympha* or Juice, which the Infundibulum derives from the Plexus Choroides and pi- neal Gland ; and from this Lympha does the Gland take its Name. See Infundieulum, &c.

between the two-, and conceive it to be the Situation of a

Body among adjacent Bodies confider'd as at reft Thus

tteTower (hall be deemed to remain in the fame Time, tho the ambient Air be changed, fince it retains the fame Situation, with regard to the neighbouring Hills, Trees, and other Parts of the Earth.

Sir Ifaac Newton better and more intelligibly diftinguifhes Place into Abfalute and Relative.

Abfohte and Primary Place is that Part of infinite and im-

It alfo filtrates a Juice itfelf; feparating from the Blood, movable Space which a Body poffeffes. See Ab

a white Liquor very fubtile, and apparently very fpirituous, See Spirits.

M. Lime obferves a Sinus, or Refervoir, of Blood, which touches this Gland -, and which is open to it in the Place of Contaft, fo that the Gland lies partly in the Blood. —This, that Author takes to do the Office of a Balneum Ma- ris, in keeping the Gland in the Degree of Warmth necef- fary for the Difcharge of its Functions.

This Gland is found in all Quadrupeds, Fifhes, and Fowls, as well as in Men.

M. Littre gives an Inftance of a tedious Difeale; and at

Relative or Secundary Place is the Space it poffeiTis confi-

dered with regard to other adjacent Objects Dr. Clarke

adds another kind of relative Place, which he calls relative- ly common Place, and defines it that part of any movable or meafurable Space which a Body poffeffes, which Place moves together with the Body. See Motion.

Place, Mr. Locke obferves, is fometimes likewife taken for that Portion of infinite Space poffefs'd by the material World ; tho' this, he adds, were more properly call'd Ex- tenfion. See Extension.

The proper Idea of Place, he fays, is the rehtive Pofi-

length Death, arifing from an Obftruction and Inflammation of tion of any thing, with regard to its Diftance from certain

this Gland.

PIVOT, a Foot, or Shoe of Iron, or other Metal, ufu- ally conical, or terminating in a Point ; whereby a Body, intended to turn round, bears on another fix'd at Reft, and performs its Circumvolutions.

Large Gates, &c. ufually turn on Pivots.— The Ancients tell us, they had Theatres in Rome that held Eighty thoufand People; which yet turn'd on afingle Pivot. See Theatre and Amphitheatre.

PLACARD, orPLACART, otPlacaert, afo-

fix'd Points-, whence we fay, a thing hasor has not chang'd Place, when its Diftance is not alter'd with refpifl: to thole Bodies.

For the Vifwn of P t a c e. See Vision.

Place, in Opticks, or Optic Place, is the Point to which the Eye refers an Object. See Optic.

Thus the Points D and E (Tab. Optics, j>g. 68.) to which two Spectators in D and E refer the Object C, are call'd Optic Places. See Vision.

Here, if aright Line joining the Optic Places D and E, be

reign Term, frequent in Gazettes, tho' fcarce yet natura- parallel to a right Line paffing thro' the Eyes of the Speft

,• rj Tnrc A R- *tiA I~\: IT-., .. .... ~C .i__ r\..- m r^ r. '•.. i

liz'd.

It fignifies a Leaf, or Sheet of Paper, ftretch'd and ap- plied upon a Wall, or Poft. Edicts, Regulations, &c. are

to be made publick in Placards.

The Word Placard is alfo ufed for a Libel, or Lampoon. —At Rome, Placards againft the Pope are frequently fix'd in the Night-time, to the Statue of Pafquin. See Pasqui- nade.

Placard, in Architecture, the Decoration of the Door of an Apartment ; confiding of a Chambranle, crown'd with its Frieze or Gorge ; and its Corniche fometimes fup- ported by Confoles. See Door.

Placard, In our Cuftoms, a Licence whereby a Per- Ibn is permitted to (hoot in a Gun > or to ufe unlawful Game. See Game.

PLACE, Locus, in Philofophy, that Part of immovable Space which any Body poffeffes. See Body and Space.

tors A, B •, the Diftance of the Optic Places D, E will be to the Diftance of the Speftators A and B, as the Diftance of one of the Optic Places from the Place of the Object EC, to the Diftance of the other Spectator from the fame Object A C.

Optic Pl a c e of a Star, is a Point in the Surface of the Mundane Sphere, as C or B, (Tab. Astronomy Fig. 27.) where- in a Spectator in E, or T, fees the Center of the Star S. See Star and Planet.

This is divided into true and apparent.

True or real Optic P L A c E is that Point of the Surface of the Sphere, B, wherein a Spectator, placed in the Center of the Earth C, fees the Center of the Star or Phenome- non Or a Point among the fix'd Stars, determined by a

Line drawn from the Center of the Earth, through that of theStar,and terminated in C among the Stars. SeeSPHERE.

Apparent or vijible Optic Place is the Point of the Sur-

Ari/totle and his Followers, divide Place into External and face of the Sphere, wherein a Spectator, placed on the Sur- face of the Earth E, fees the Center of the Star S. Or a

Point found by a Line paffing from the Spectator's Eye through the Star, and terminated in the Sphere of the Stars.

The Diftance between the two Optic Places is what we call the Parallax. See Parallax.

P L k c n of the Sun, a Star, or Planet, (imply, denotes the Sign and Degree of the Zodiack, which the Body is in.' See Sun, Star, &c.

Or, it is that Degree of the Ecliptic, reckoned from the Beginning of Aries, which the Planet's, or Star's Circle of Longitude cuts ; and therefore coincides with the Longi- tude of the Sun, Planet, or Star. See Longitude.

As the Sine of the Sun's greateft Declination, 23° 30': to the Sine of any prefent Declination given or o'oferved, ■v. g. 23 15' : : fo is Radius : 10. To the Sine of his Lon- gitudegi 52'i which if the Declination wereNorth, would give 20 52' of Gemini, If South 20° 52' of Capricorn, for the Sun's Place. See Planet.

Moons Pl ac e is that Point of her Orbit wherein (he is found at any Time. See Moon and Orbit. _ This, byreafon of the great Inequalities in the Lunar Mo- tions, which render a Number of Equations a«d Reductions necelfary e'er the juft Point be found, is of various kinds ; viz.. her fictitious Place, which is the Moon's Place once e- quated ; her Place nearly true, which is her Place twice e- quated; and the Moon's true Place, which is her Ware thrice equated. See Equation.

Eccentric P L a c e of a Planet in its Orbit, is the Place, or Point of its Orbit, wherein a Planet would anpear if feen from the Sun.

Thus fuppofe N E R the Ecliptic, N P Q.the Planet's Orbit, the Sun in S, the Earth in T, and the Planet in P ; the right Line S P expreff-s the Eccentric Place m the Orbit.

Internal.

Internal Place is that Space or Room which the Body fills

or contains External is that which includes or contains

the Body ; call'd by Ariflotle, the firft or concave and im- movable Surface of the ambient Body.

'Tis controverted in the Schools, whether Internal Place be a real Entity, or only an imaginary Being; i. e. whether it be anything intrinfically ; or only an Aptitude and Capacity of receiving Bodies.

Some maintain it a pofitive Being, Incorporeal, Eternal, Independant, and Infinite ; and affert it to be no other than the lmmenfily of the Godhead.

The Cartefians, on the contrary, hold Internal Place, ab- ftraflly confijer'd, to be no other than the very Extenfion of the Bodies contained therein ; and therefore in no wife different from the Bodies themfelves.

The Schoolmen likewife difpute whether External Place be movable or immovable. Its Immobility is argued from this Confideration, that what moves mud neceffarily leave its Place, which it cannot do if it go along with the movable. Others charge an Abfurdity on this Opinion of Ariflotle, viz.. That hence it follows, that a Body really at reft is continually fhifting Place : A Tower, for inftance, on a Plain, or a F^ock in the middle of the Sea, in regard the one and the other are continually inclofed with new Air or new Water, mult be faid to be in Motion, or to change Place.

To' falve this Difficulty, and ward off the Abfurdity which follows from Ariftotle's laying down External Space as im- movable ; infinite Expedients have been had recourfe to — The Scotijls contend for Place's being immovable, by Equi- valence. Thus, when the Wind blows, the Air which in- verted the Surface of the Tower does indeed recede, but then other fimilar and equivalent Air takes place — TheTZw- m//hchufeto deduce the Immobility of External Place, from keeping the fame Diftance from the Center, and the Car- dinal Points of the World. The Nominalifls, from aCor-

refpondence with certain virtual Parts of the Divine Immen- fity.

The Cartefians deny External Place to be either a fur- lounding Surface, or a Body furrounded, or a meaa Term

Heliocentric Place, of a Planet, or its P L a c e redu- ced to the Ecliptic, or the Eccentric Place in the Ecliptic, is that Point of the Ecliptic to which a Planet, view'd from the Sun, is referr'd. See Heliocentric.

This coincides with the Longitude of a Planet view'd from the Sun. See Longitude,

Thus