Page:Cyclopaedia, Chambers - Volume 2.djvu/203

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Minute, is fpcaking of Weights, is the 24th part of a Grain. See Grain.

Minute is alfo ufed to fignify a Jhort Memoir, or Sketch of any thing taken haflilyin writing.

In this fenfe we fay, the Minutes of the Proceedings of the Houfe of Lords, iSc.

The Word comes from the Lathi Minutus, fmall.

M1QUELETS, a kind of foot Soldiers, inhabiting the Fyrenean Mountains ; arm'd with l J iftols under their Belts, a Carbine, and a Dagger.

The Mquelets are dangerous People for Travellers to meet.

MlRABOLANS, or Mirobolans, in Pharmacy. See Myrobolans.

MIRACLE, in the popular fenfe of the Word, is a Pro- digy, or an extraordinary Event that furprizes us by its Novelty.

In the more Accurate and Philofophical Senfe, ^Miracle is an Effect that does not follow from any of the known Laws of Nature ; or which is inconfiftenr with fome known Laws thereof. See Nature.

AMiraclc, therefore, being a fufpenfkm of fome Law, can't come from any hand lefs than his who fix'd that Law. See Gor, Law, &c.

Sptnofa denies thai any Power can fuperfede that of Na- ture j or that any thing can dillurb or interrupt the Order of Things ; and accordingly defines a Miracle to be a rare Event, happening in cunfeqaence of fome Laws that are unknown to us. See Spinosism.

The Divines define a Miracle to be an extraordinary and wonderful EftVct, above the Power of Nature, wrought by God, to manrreft his Power or Providence '-, or to give Credit to fome M. ffenger fent from himfelf. Thus Jefus ChrKt evinced the Truth of his Miflion, and his Doctrine by Miracles $ and thus alio did Mo/if.

It is Hill a difpu'te in the World, how far it may be in the power of the Devil to work Miracles j or wherein the fpecrfic difference lies beiween the Miracles of Mofes, and thofe of Pharaoh's Magicians '-, thofe of Jefus Chrift and the Apoftlt*, and thofe of Simon Magus and Apollonius Tyaiueus : Whether the latter were any more than mere Delufionsof the Senfes ; or whether any fupernatural and diabolical Power concurred with them. See Magic.

The Church of Rome abounds in Miracles 5 if we believe their Writers, fome of their Monks have wrought more Miracles than all the Apofiles j and that without any vifible 3>leceflity for them.

As full as that Church pretends to be of Saints, it is a Rule with them, that none are ever Canonized till there be good Proof of his having wrought Miracles. So that v/ere all thofe allowed good Miracles, and to have happened out of the common Order of N ature, they are fo numerous, one would be tempted to think there were no Order or Law of Nature at all. See Saint.

There are thofe however, who fet afide the Authority of ftll Miracles j thinking it unbecoming the Wifdom ofGod to eftablifh fuch Laws, as that he fhould find it frequently neceffary to fuperfede. And as the former, from the avowed Authority of fome Miracles, fetch an Argument for the Truth of all j pleading thofe which areallow'd as well as thofe which are quehion'd 5 fo thefc ailed ge the falfe ones as conclufiuns again!) them all.

The Romans attribute Miracles to their Emperors Adrian and Vejfafian.

St. Auvufhne is a ftrong Advocate for Miracles. He men- tions feveral whereof he was an Eye-Witnef?, and others whereof he was informed by thofe that were. In the fingle City of Bippo, he tells us there were feventy Miracles wroughtin hefpace of two "Years, on the building a Chap- pel in honour of St. Stephen.

Tho Miracles may prove the Superintendency of a volun~ tary Agent ; and that the Univ rfe is not guided by Ne- ceffny or Fate ; yet that Mind mufl: be weak and inadver- tent, which needs them to confirm the Belief of a Wife and Good Deity : Since the Deviation from general Laws, un- lefs upon very extraordinary Occxfions, mufl be a Preemp- tion of Inconstancy and Weaknefs, rather than of a fteady Wifdom and Power ; and mult weaken the be ft Arguments we have for the Sagacity and Power of the Univerfal Mind. Inquiry into the Original of the Ideas of Beauty, &c.

MIRROR, or Mirhoue, or Speculum, Body which exhibits the Images of Objects presented thereto, by Re- flexion. See Reflexion.

The Ufe of Mirrours is very antient. Mention is made of a Brazen Mirrour, or Looking-Glafs in Exodus xxxviii. 8. where Mofes is fu id to have made a Brazen Lamer, or Bafon, of the Looking-Glaffes of the Women continually affembled at the Door of the Tabernacle. 'Tis true, fome modern Commentators will not allow the Mrrours themfelves to have been Brafs 5 butofGlafs, only kt, or framed in Brafs. But the moft learned among the Rabbins do all allow, that in thofe times, the Mrrours made ufe of by the Hebrew Women in dreffing their Heads, were of Metal ; and that the devout Women

mention'd in thisPaffage, made Pre fen ts to Mofes of all thcit Mirrours to make the Brazen Laver. See the Jefuit Bonfrezius's Comment on this Text.

It might likewife be proved, that the Antient Greeks made ufe of Brazen Mirrours 5 from divers PaiTages among the antient Poets. See BuRNiNG-Mirnwr.

Mirrour, in Catoptrics, isany poliflYd Body impervi- ous to the Rays ot Light, and which of conference reflects it equally. See Light.

Thus Water in a deep Well or River, and fmooth polite Metals, arc rank'd among the number of Mirrours.

In this fenfe, the Doctrine of Mirrours makes the Sub- ject of 'Catoptrics, See Catoptrics.

Mirrour, however, in the more confined Senfe of the Word, is peculiarly ufed to iignify a fmooth Surface of Glafs, tinn'd or quick- filver'd on the back -fide, which ex- hibits the Images of Objects oppofed thereto.

The VoBrine of Mirrours is built on the following general Principles.

1. Light refieBedfrom any Mirrour, or Speculum, makes the Angle of Incidence equal to that of Reflexion 5 which fee de- nion ft rated under the Word Reflexion.

Hence, a Ray of Light, as A B (Tab. Optics, Fig 26".) falling perpendicularly on the Surface of a Speculum, will be reflected back, uponitfelf; which we find by Experience it actually does.

From the fame Pointof a Mirrour, therefore, therecan't be feveralRays reflected to the fame Point 5 fince in that Cafe, all the Angles of Incidence mufl be equal to the fame Angle of Reflexion C B G, and therefore ta eacho- otherj which is abfurd. Nor can the Ray A B be reflected into two or more Points ; fince, in that Cafe, all the Angles of Reflexion would be equal to the fame Angle of Incidence A B F : which is likewife abfurd.

z. From every Point of a Mirrour, are reflected Rays thrown 071 it from every F nit of a radiant OhjeB.

Since then Rays coming from different parts of the fame Object, and flriking on the fame Point of the Object, cannot be refle&ed back to the fame Point ; the Rays which flow from different Points of the fame radiating Object, are again fepar&ted after reflexion ; fo that each Point ihews whence it came. See R adi Ant.

Hence it is, that the Rays reflected from Mirrours exhi- bit the Objects to view. Hence, alfo, it appears, that rough uneven Bodies mufl reflect the Light in fuch manner, as that Rays coming from different Points, will be blended or thrown confufedly together.

Mirrours are either Plane, Concave, Convex, Cylindri- cal, Conical, Parabolical, or Elliptical,

Plane Mirrours, or Specula, are thofe which have a plain or flat Surface. See Plane.

Thefe, by a popular Word, we call Looking-Gla/Jes.

For the Manner of making plain Mirrours, or Specula, fee Look inc-Gl ass.

Laws and Phenomena of Plain Mirrours.

1. In a plain Mirrour, every Point of an Ob jeS, as A, (Tab. Optics, Kg, 27.) isfeen m the htterfeUion of the Cathetus of Incidence, A B, with the refleB edRay CB.

Hence, 1. As all the reflected Rays meet with the Ca- thetus of Incidence in B j by whatever reflected Rays the Point A be feen, it will {till appear in the fame Place. Confequemly, any number of Perfons viewing the fame Object in the lame Mirrour $ will all feeit in thefame place behind the Mirrour. And hence it is, that the fame Ob- ject has only one Image, and that we don't fee it double with both Eyes. See Vision.

2. Thediflance of the Image B, from the Eye C, is compounded of the Rav of Incidence A D, and the re- fleacd Ray C D : And "the Objeft A radiates reflected- ly, in the fame manner asit would do directly, were it removed into the place of the linage.

II. The Image of a radiant Point, B, appears juft fo far behind a plain Mirrour, as the radiant Point is before it.

Hence, 1. If the Mirrour A G be placed horizontal j the Point A will feein fo much below the Horizon, as it is really elevated above it : Confequently, erect Objects will appear as if inverted ; and therefore Men Handing on their Feet, as if on their Heads. Or if the Mirrour be faftned to the Ceiling of a Room, parallel to the Horizon, Objects on the Floor will appear above the Ceiling as much as they really are below it ; and that upfide down.

III. In a plain Mirrour, the Images are per feBly Similar, and equal to the ObjeBs. And hence their Ufe as Looking- Glaffes.

IV. In a plain Mirrour, things en the right Hand, appear as on the left 5 and vice verfa.

Hence alfo, zae have a Method of Meafuring any inacceffble Altitude by means of a plain Mirrour.

Thus, the Mirrour being placed horizontally in C, Fig. 28. retire from it till fuch time as theTop of the Tree be feen

therein.