Page:Cyclopaedia, Chambers - Volume 2.djvu/611

 REP

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REP

REPEAT, in Mufick, a Character fiiewing that what was laft play'd or fung, muft be repeated, or gone over again. See Re- petition.

The Repeat ferves inftead of writing the fame thing twice o- ver,— There are two Kinds of Repeats; the great and the [mall

The firft is only a double Bar, dotted on each Side; or two parallel Lines drawn perpendicular a-crofs the Staff} with Docts on either Hand : See i:s Form under Characters of Mufick.

This Mark mews that the preceding Strain is to be repeated; that is, if it be near the Beginning of the Piece, all hitherto fung, or play'd, is to be repeated; or if towards the End of a Piece, all from fuch another Mark.

In Gavots, we ufually find the Repeat, at about the third Part of the Piece.— In Minuets, Borees, Courants, &c. towards the End.

Some make this a Rul?, that if there be Dotts on each Side the Bar, they direct to a Repetition both of the preceding and the following Strain; if there be only Dotts on one Side then, only the Strain on that Side to be repeated.

The [mall Repeat is where only fome of the laft Meafures of a Strain are to be repeated.— This is denoted by a Character fet over the Place where the Repetition begins, (fee Characters in Mufick) and continues to the End of the Strain.

When the Song ends with a Repetition of the firft Strain, or Part of it, inftead of a Repeat, they u(e the Words da Capo, i. e. from the beginning.

REPELLENT, Repellents, in Medicine, aRemedy which repels or drives back a morbid Humour into the Mafs of Blood, from which it was unduly fecretcd. See Humor and Medi- cine.

Or, Repellents are Medicines which prevent fuch an afflux of the Fluids to any particular Part, as will raife it into a Tumour; or drive them back when they are collected. See Tumor.

To form an Idea of the Manner of their Operation, it may be obferv'd, that all Tumors arife either from an increafe in the Ve- locity or Quantity of the Fluids, or a Weaknefs in fome particu- lar Part ; though fometimes both concur. — Now an increafe in the Velocity of the Fluids makes them more forcibly pufh a- gainft, and diftend all the Parts in their Circuit ; if therefore any Part be unequally prefled or relaxed by external Injuries, that will be more elevated than any other ; and for want of equal Re- finance with the reft of the Body, will at length receive fuch a Quantity of Fluid, as will raife it into a Tumor, efpecially if any of its Veflels be obftructed : Becaufe the Protrufion of frelh Mat- ter, a tergo, will continue to add thereunto, till the Part is on the utmoft ftretch, and can hold no more. See Blood.

In this Cafe, all thofe Means are faid to be repellent, which check the growth of the Tumor, and ailift the refluent Blood in taking up the obftructed Matter, and waihing it again into the common Stream.

This Intention is chiefly favoured by Evacuation and Revul- fion; for wbatfoever Ieflens the Quantity of the Fluid, wilt di- minifti the force upon the tumefied Part.— But it concerns us moft to know how external Application to the Part itfelf, helps this Affair.

Herein a Medicine comes to be repellent, by confiding of fuch fubtile Parts, as may tranfmit fome of them through the Pores, and help to render the obftructed Matter more fluid, fo that it comes the more eafy to be loolened, and fall again into the cir- culating Current.— But in this Cafe there is a Hazard of fuch things likewife putting the obftructed Humour into a Ferment, whereby it fooner turns into Pus, and then they come under the Denomination of Suppuratives or Ripeners. See Suppura- tive.

What, therefore, in the moft ftricl: Senfe, is to be reputed a Repeller, is that which aitringes and ftrengthens the Part, fo as to make it relift any fuch Lodgment. See Astringent and Strengthener.

Thefe are fuch whofe Qualities are moft manifeft in their Coldnefe, and drying Properties : But there are fo few Inftances wherein Bandage is not better than fuch Application, that very little comes to be ufed for that purpofe. In Hemorrhages, and Ouxings out of Serum, fo as to deform the Skin ; Simples of this Nature moftly take place; which anfwer their Ends in aftrin- ging the Fibres, whereby thofe Apertures are fo clofed, as not to admit through them afterwards any fuch fluid.

Some things alfo anfwer this End only by ftimulating the Fi- bres of the tumefied Part, fo as to give them fudden and forci- ble Twitches, whereby the obftru&ion is fometimes loofened and {hook away, as it were, into the refluent Current. — Such a fort of Motion will be occafioned by the fudden Applicatinn of any thing extreamly cold, as common Water; but the Practice is fel- dom fafe, becaufe if the firft Efforts which the Fibres are put upon by thofe means, do not fucceed in breaking away the in- clofed Matter, they will be ftrained, and not able afterwards to repeat their natural Vibrations : The Confequence of which is ■weakening the Part, which will render the Tumor more obfti- nate.

REPELLING Power, Vis Repellens, in Phyficks, is a certain Power or Faculty refiding in the minute Particles of na- tural Bodies, whereby they mutually fly from each other. Sec Pews* and Particle.

This Power is the reverfe of the Attractive Power'. See At- tractive.

Sir Jfaac Newton having eftablifhed the attractive Power of Matter from Obfervation and Experiment; argues, that as in Al- gebra, where pofitive Quantities ceafe, there Negative ones com- mence ; fo in Phyficks, where the attractive Force ceafes, there a repelling Force muft begin.

But that there is fuch a Force does likewife appear from Ob- fervation. See Repulsion.

As the repelling Power feems to arile from the fame Principle as the attractive, only exercifed in different Circumftances ; 'tis govern'd by the fame Laws : Now the attractive we End is ftronger in fmall Bodies than in great ones, in Proportion to the Mafles.— Therefore the repelling is fo too. But the Rays of Light are of all others the moft minute Bodies we know of; therefore of all others their repelling Force muft be the ereateft. See Ray. &

Sir Ifaac Newton computes that the attractive Force of the Rays of Light is above iooooooooooooooo times as ftrong as the Force of Gravity on the Surface of the Earth : Hence ari- fes that inconceivable Velocity wherewith Light muft move, to reach from the Sun to our Earth in (even Minutes. For the Rays emitted from the Body of the Sun by the vibrating Moti- on of its Parts, are no fooner got without the Sphere of Attracti- on of the Sun, than they come within the Action of the re- pelli?ig Power. See Light.

The Elasticity, or fpringineis of Bodies, or that Property where- by after having their Figure alter'd by any external Force, they return to their former Figure, follows from the repelling Power. See Elasticity, Air, &c.

REPERCUSSION, in Mechanicks, See Reflection.

Repercussion, in Mufick, a frequent Repetition of the fame Sounds. See Repetition.

_ This frequently happens in the Modulation ; where the effen- tial Chords of each Mode, or of the harmonical Triad, are to beat oftener than the reft ; and of thefe three Chords the two Extremes, /". e. the final and the predominant one, (which are properly the RepercuJJton of each Mode) oftener than the middle One.

REPERTORY, Repertorium, a Place wherein things are orderly difpofed, fo as to be eafily found when wanted-

The Indices of Books are Repertories, (hewing where the Mat- ters fought for are handled. See Index.

Common Places are a kind of Repertories, very uteful to the learned. See Common Place.

Repertorium Anatomhum, is a large Hall near an Amphitheatre of Diffedtions, where Skeletons both human and brutal, are or- derly preferved.— Such is the Repertory of the French King's Gar- den at Paris.

REPETITION, Repititio, the re-iterating of an Action, See Reiteration.

Habitudes are acquired by the frequent Repetition of Actions.' See Habit.

Mulicians and Comedians make fevera! Repetitions of their Con- forts and Comedies, e'er they perform for good. See Rehearsal.

The School Philofophers call the Repetition of the fame nu- merical Effect in another Place, the Replication of that Effect- See Replication.

Repetition, in Mufick, a re-iterating or playing over again of the lame Part of a Compofition ; whether it be a whole Strain, a Part of a Strain, or a double Strain.

The Repetition is denoted by a Character, called a Repeat, which is varied fo as to exprefs the various Circumftances of the Repe- tition. See Repeat.

When the Song ends with a Repetition of the laft Strain, or a part of it; ihcRepetition is denoted by da Cipo; that is, from the Beginning.

Repetition, Reply, Is alfo ufed in Mufick, when after a lit- tle Silence, one Part repeats or runs over the fame Notes, the fame Intervals, the fame Motions, in a word, the fame Song, which a firft Part had already gone over during the Silence of this.

Repetition, Reply is alfo a doubling, or trebling, &c. of an Interval; or a Reiteration of fome Confonance or Diffonance: Thus a fifteenth is a .Repetition of the Odtave, i. e. a double Octave or fecond Otfave. See Octave.

Repetition, in Rhetorick, a Figure whereby the Orator rc- hearfes the fame Word or Phrafe over again.

Of this there are two Kinds.— In the firft, the Word is repeat- ed precifely in the fame Senfe : As, Oh, Jerufalem, Jerujhlem y who killeft the Prophets, &c. my God, my God, why haft thou for fa ken me.

Such Repetitions have the fame effect in Difcourfe, with fecond ftroaks of the Pencil in Painting ; they render the Colours more ftrong and lively.

Sometimes the Orator begins again and again with the fame Word ; of which we have an Inftance in the beginning of Cice- ro's firft Oration againft Cat aline: Nihil ne te Notlurnum pr^fidium pahtii, nihil urbis Vigiha, nihil timor populi\ nihil Conjenfus bonorum omnium, nihil hie Munitijjlmus babejtdi Senatus locus, nihil horum or a vultuffj tnoverujtt ! Where the Word nihil fo often re-iterated gives an admjrable Force and Vehemence to the Difcourfe.—

Again,