Page:Cyclopaedia, Chambers - Volume 2.djvu/453

 POI

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Points/ Reflexion, is a Pwrt ori the Surface of a Glafs or other Body whence a Ray is reflected. See Refle- xion. ,

Point of Refrallion, is a Point in the Surface of a Glals or other refrafling Surface, wherein the Refraction is effected. See Refraction.

Points, in Heraldry, Divifions of the Efcutcheon into feveral Squares, fometimes to the Number of 9, fome- times to 15 ; fome whereof are of one Colour or Metal, the Others of another ; called alfo Equipollent Points.

There is alfo another Divifion of the Efcutcheon into Points, which have feveral Names and Values, according to their feveral Places. _

There are nine Principal Points in an E- fcutcheon; as mark'd in the Figure adjoin- ing— A reprefents the dexter Chief Point. — B the middle Chief 'Point.— C the [milter Chkf.—D the Honour Point.— E the ft/} Pomr, call'd alfo the Center —F the Norn- bril or Navel Point.— -G the Dexter Safe. 1 the Sinister £afe.—H the precife middle Bafe. See each further defcribed in its Place. Colombicre makes the Points and their

Situations fymbolical As the feveral

Bearings in an Efcutcheon are fo many Types reprefenting the commendable Aaions of the Peribn they are given to; fo the Efcutcheon itfelf reprefents the Body of the Man that perform'd them, and the Points, or Parts, ligniSed by thefe Letters, the principal Parts of his Body — Thus, A, B, C re- prefent the Head, in which the three great Faculties refide : D, the Neck where Ornaments are chiefly bore : E, the Heart, &c. See Escutcheon.

Pol nt is alfo an Ordinary, fomething like the Pile, nfing from the bottom of the Efcutcheon to the Top-, very nar- row, and only taking up two Thirds of the Point of the Efcutcheon.— When it thus rifes from the Bafe, it is peculi- arly call'd Point- in- point. .

Point inverted, is when it defcends from the Chief down- wards; pofMing two thirds of the Chief, but diminilhing as it approaches the Point of the Efcutcheon, tho' without touching it. .,,„.,

Point en Band, or Point en Bane, is when the Point is pi iced

tranfverfe, in the Situation of a Bend or Bar. When it

comes from the Sides of the Efcutcheon, it is alfo call'd a Point Dexter or Sinijler, according to its Situation.

The Point Dexter is commonly reputed an Abatement due to a Braggadocio.— Point-Champion-Ten due for killing a Prifoner after Quarter demanded Point in Point, a Di- minution belonging to a Coward Point plain, an Abate- ment belonging to a Lyar, &c. See Abatement, Dimi- nution, &c. •

Point is alfo ufed in Heraldry, for the lower part of the Efcutcheon, which ufually terminates in a Point. See Escutcheon.

In the French Arms the Flower de Lys's are two in Chief and one in Point.

Point, is alfo an Iron or Steel Inftrument, ufed with fome Variety in feveral Arts.

Engravers, Etchers, Wooden Cutters, Stone Cutters, &c. life Points to trace their Defigns on the Copper, Wood, Stone, &c. See Engraving, Etching, &c.

Statuaries, &c. have likewife Points in manner of little Chiflels, ufed in the firft forming or sketching out their Works. See Statue, Foundery, &c.

Turners work or falbion their common Works between

two Points faftened to the Puppets Lapidaries have Iron

Joints, to the Ends whereof are faftened Pieces of Diamonds, ferving to pierce the precious Stones withal. See Turning, Lapidary, &c.

Point, in the Manufaftories, is a general Term ufed for all kinds of Laces wrought with the Needle;— Such are Point de Venice, Point de France, Point de Genoa, &c. which are diftinguifh'd by the particular OEconomy and Arrange- ment of their Points.

The Word is fometimes alfo ufed for Lace wove with Bobbins; as, Englifi) Point, Point de Malines, Point de Havre, &c.

Point, in Poetry, is a brisk lively Turn, or Conceit, ufiially fotmd or expected, at the Clofe of an Epigram. See Epigram.

PoiKT-iiWi in Gunnery, denotes a Shot or Bullet to go directly forward, in a ftrait Line, to the Mark ; and doth not move in a Curve, as Bombs and highly elevated random Shots do. See Mortar, Projectile, Gunnery,

ijfc.

POINTED— A Cto(s pointed, is that which has the Ex- tremities turn'd off into Points by ftrait Lines. Cohmbiere. calls it aiguifee See Cross.

P O I N T 1 N G the Cable, is a Sea-Term, denoting the un- twifting it at the End, and leflening the Yarn, and twifting them again, making all fall with a Piece, of Marline, to keep {I from ravelling put, JieeXABis,

Pointing; in Grammar, the Art of dividing a CS courfe, by Points, into Periods and Members of Periods ; to facilitate the Pronunciation and Underftanding thereof. See Punctuation.

Pointing, among Seamen, the marking on the Chart in what Point or Place theVeffelis. See Chart, Rhumb, &c.

All the Difficulty in pointing a Chart arifc from our Igno- rance of the Longitude— The Pilot eafily finds the Latitude by taking the Height of the Pole ; but for the Longitude there is no coming at it but by Computation which is ever uncertain. See Longitude, Latitude, Sailing, &c.

Pointi ng, in War, the levelling or directing of the Cannon or Mortar-Piece, fo as to play againft any certain Point. See Levelling, Cannon, Ordnance, Mortar, Projectile, &c.

This is done by means of a Quadrant with a Plummet. See Gunners Quadrant.

POISON, in Medicine, a malignant Quality in fome Animal, Vegetable or Mineral Body, which renders it hurt- ful, and even mortal to thofe who take it.

Some define a Poifon to be any thing taken inwardly, whofe Properties are contrary to thofe of a Food, or to what they fhould be in order to Nutrition. See Food.

Poifons are of various lands; and operate in various manners : fome by diffolving the Blood, others by coagula- ting it; and others by corroding and deftroying the folid Parts. See Blood, Dissolution, Coagulation, Cor- rosion, r>c,

Some attack, equally, all the Parts ; fome only a particu- lar one Thus the Lepus Marimis is an Enemy to the

Lungs, Cantharides to the Bladder, &c. Some again, which prove Poifon to Man ferve for Food to

other Animals. Thus Aiandragora and Jufquiamnus feed

Hogs, kill Man ; and thus that deadly Poifon Hemlock is wholefome for Goats, Buftards, and, is Galen fays, for Star- lings too. The Cajjada Plant, Sir Hans Sloane tells us, poi- fons, unprepared ; but prepared is the very Bread of the IVefl Indies ; particularly Jamaica and the hotter Parts ; and is ufed to victual Ships. Nay, what is more, fome Poifons are not only Food, but

even Phyfick to other Animals In the Phil. Tranfalr. we

have an Inftance of a Horfe troubled with the Farcy, which could not be cured by the molt famed Remedies, which yet cured himfelf in a fhort time, by feeding greedily on Hemlock. —Fontanus tells us of a Woman who eat Hemlock for fome time to procure Sleep; and with very good Effect; tho' re-; peated Dofes of Opium had no Operation.

Dr. Tone. Robwfon, in a Letter to Mr. Ray, gives an Ac- count of feveral poifonous Plants, which if truly corrected, or exactly dofed, he fays, may prove the moft powerful Re- medies known.— — Thus the Hellebores incorporated with a Sapo, or Alkaly- Salts alone, are fuccefsful in Epilepfies, Ver- tigo's, Pallies, Lethargies, and Mania's. Dofe from g;. to 5/r. The Roots of Cicuta, Ajfarum, and Napellus, in Agues and periodical Pains: Dofe ej. to sfs. The Hyofcyamus in Hse- morrhagies, violent Heats and Inflammations: Dofe ej. to ?/}. The Semen Stramoni* is a good Anodyne, ufeful in Vigilia's, Rheumatifms, Hyfteric Cafes, &c. Dofe ej. to 3/}. Elatcrium, Soldanella a- Gratiola, in Hydropic Cafes. Opium corrected lofes its Narcotic Quality, and is fafely given ia great Dofes in convullive Cafes, Fluxes, Cartarrhs, &c.

The Word Poifon is derived from the Latin Potio, Draught, and was antiently ufed in an innocent Senfe. See Potion. Phyficians diftinguifii three Kinds of Poifons: Animal Poi- fons; i.e. thofe drawn from Animals; as the Viper, Afpic, Scorpion, Lepus Marinus, &c. See Viper.

Vegetable Poifons, as Aconite, Cicuta, or Hemlock, Hellebore^ Napellus, &c. See Aconite, Cicuta, Hellebore, &c. And Mineral Poifons, as Arfenic, Corrofive Sublimate, Ce- ruffe, Orpiment, Rcalgal, &c. See Arsenic, f>c.

The Theory of the Effects, Operations, &c. of Animal Poifons, is very accurately and mechanically delivered by Dr. Mead; in thofe remarkable Cafes, the Bites of a Viper, Tarantula, and a mad Dog. See his Doctrine under the re- fpeftive Articles, Tarantula, Vipeji, and Hydrophobia. The Operation of vegetable Poifons, fee deliver'd under the Article Opiates.

As to Mineral Poifons, they all bear fo much Analogy to that made of Quickfilver in the common Sublimate, that their O- peration will eafily be conceiv'd from what we have already; laid down under the Heads, Mercury and Sublimate.

They are all more or lefs dangerous, as their Salts receive a greater or lefs Force from the metallick Particles; and hence, as the molt virulent may be mitigated by break- ing the Points of the faline Cryftals ; the molt innocent Minerals may become corrofive by combining them with Salts, as is feen in the Preparations of Silver, Antimony, Iron, &c. See Mephites, Grotto, &c.

The general Remedies againft Poifons are known by the Name of Antidotes, Alexipharmich, AlexiteriaU t Sec. See A.NTIB.OTE, AlfcXIPHARMIC, &<i

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